The Qur'an almost equates jihad, an important Islamic duty, with Islam. The most distinguished servants of God, whether Prophets or saints, have attained their distinction through jihad against unbelievers and against their own carnal selves. Jihad has a great worth in the sight of God, because He created us to strive so that we might discover our true being and encourage others to do likewise.
God decrees in the Qur'an:
Those believers who sit at home, other than those who have a disabling hurt, are not equal with those who strive in the way of God with their possessions and their selves. God has conferred on those who strive with their possessions and their selves a rank over those who sit at home; yet to each, God has promised good, but He has be stowed on those who strive a great reward above those who sit at home. (4:95)
People have diverse careers, and their objectives in those careers allow others to assess their standing. But what is our end? Whatever our rank or occupation, each person was created from a drop of fluid and will end as a corpse.
This is true of everything except for the work of Prophethood, for its reward multiplies until the Day of Judgment. Prophethood contains some spiritual quality that is not touched by mortality. A Prophet seeks to enable people to know God and thereby reach eternity. We were not created to be subjected to physical corruption and dissolution, along with everything else in this world. In fact, our deepest natural tendency is toward eternity, and it is the Prophets who alert, educate, and cause us to realize this tendency.
In the sight of God, Prophethood is the most sacred work entrusted to humanity, and jihad expresses this aspect of it. Due to its importance, the Qur'an distinguishes those Muslims who swore to the Prophet that they would perform jihad: Those who swear allegiance to you, swear allegiance only to God. The hand of God is above their hands. So whoever breaks his oath, breaks it only at his own peril; while whoever keeps his covenant with God, on him will He bestow immense reward (48:10).
This verse was revealed when the Messenger told the Muslims they would return to Makka and make pilgrimage. So they set out as pilgrims for Makka. But when they reached Hudaibiyya, the Makkan polytheists refused to let them pass and threatened war. This unexpected objection shocked the believers, who regarded it as a heavy blow to Islam's honor. They did not know how to respond. The Messenger sent 'Uthman ibn Affan to Makka to reaffirm that they had come only to make pilgrimage and therefore in peace. The Makkan chiefs imprisoned 'Uthman and circulated the rumor of his death. This news so angered the Muslims that the Prophet demanded that they swear allegiance to him by taking his hand. God then revealed the verse quoted above.
Another verse reads:
God has bought from the believers their lives and their wealth because Paradise will be theirs. They fight in the way of God, slay and are slain. It is a promise which is binding on Him in the Torah and the Gospel and the Qur'an. And who is more true to his promise than God? Rejoice then in your bargain that you have made, for that is the supreme triumph. (9:111)
This "bargain" is the highest distinction, since whoever enters into it is being directly addressed by God.
The Messenger said: "I wished very much that I had been slain for the cause of God and brought to life to be slain again, and brought to life to be slain again." He also said: "It is better to keep one's eyes open for a day's duty, solely in the cause of God, against the danger of enemy infiltration through a pass, than to possess the world and all its contents."  We may infer from this hadith that to be alert for a day in the cause of God, against any danger that may befall the community, is better than possessing the Ka'ba—since the Ka'ba is among the contents of this world.
Another hadith tells us: "The recompense from God for one's good acts is cut off at the moment of death, except for jihad. The reward for jihad multiplies until the Day of Judgment. Further, God exempts those who have striven in His way from being interrogated in the grave." 
Jihad has two aspects: fighting to overcome carnal desires and evil inclinations (the greater jihad) and encouraging others to achieve the same objective (the lesser jihad). The Muslim army was returning to Madina after defeated the enemy, when the Messenger told them: "We are returning from the lesser jihad to the greater one." When the Companions asked what the greater jihad was, he explained that it was fighting with the carnal self. 
The aim of either jihad is to purify believers of sin so that they may attain true humanity. The Prophets were sent for this purpose:
Thus We have sent unto you a Messenger from among you, who recites unto you Our revelations (and makes Our signs known to you), and who purifies you of sin and teaches you the Scripture and Wisdom, and teaches you that which you did not know. (2:151)
We are like raw minerals to be worked upon by the Prophets, who purify and refine us by removing the seal from our hearts and ears, and lifting the veils from our eyes. Enlightened by the message they bring, we can understand the meaning of the laws of nature, which are signs of God's Existence and Unity, and penetrate into the subtle reality of things and events. Only the Prophets can guide humanity to the high status expected of them by God.
In addition to teaching the signs, the Prophets also instruct us in the Book and in Wisdom. As the Qur'an was the last Revelation to the Last Prophet, God means the Qur'an when He speaks of the Scripture, and the Sunna when He speaks of Wisdom. Therefore we must follow the Qur'an and the Prophet's Sunna if we desire to be rightly guided.
The Prophet also teaches us what we do not know, such as how to purify ourselves of sin, and we will continue to learn from him until the Day of Judgment. By following his way, many great Muslims became saints. One of them, 'Ali, said that his belief in the pillars of Islam was so firm that his certainty would not increase even if the veil of the Unseen were lifted.  'Abd al-Qadir al-Jilani is said to have had insight into the mysteries of the seventh heaven. These and many others, such as Fudail ibn Iyaz, Ibrahim ibn Adham, and Bishr al-Khafi, might well have been endowed with Prophethood if God had not sent the last Prophet already.
The dark clouds of ignorance have been removed from our intellectual horizon through the guidance of Prophet Muhammad, and many more scientific and technological advances will be made because of the light he brought from God.
 Muslim, Imara, 163; Ibn Majah, Jihad, 7.
 Kashf al-Khafa', 1:424.
 Imam Rabbani, Maktubat, 1:157.
Jihad is the legacy of the Prophets, and Prophethood is the mission of elevating people to God's favor by purifying them. This Prophetic mission is known as jihad, for it has the same meaning as bearing witness to the truth. Those who perform jihad bear witness to God's Existence and Unity by striving in His way: God bears witness that there is no god but He and so do the angels and the people of learning, maintaining justice: there is no god save He, the All-Mighty, the Wise (3:18). Such people also bear witness to the same truth in the heavenly court, where the case of unbelievers will be settled.
God bears witness to His own Existence and Unity, and those who have acquired a high level of perception can grasp the reality of this testimony. Angels bear witness to this, as they are absolutely pure in nature, as do those endowed with knowledge. Even if everybody were to deny God's Existence and Unity, the testimony of these groups is enough to establish this truth.
Those who bear witness to this truth should travel throughout the world to spread it. This was the duty of the Prophets, and it should be our duty as well:
Messengers who brought good news to humanity and who admonished them, so that they might have no argument against God after their coming. God is the All-Mighty and the All-Wise. God Himself bears witness by what He has revealed to you that it has been revealed with His knowledge; and so do the angels. There is no better witness than God. (4:165–66)
God chose a man from each nation and appointed him a Prophet. From the time of Prophet Adam, each dark era of human history was enlightened by a Prophet's message. This continued until the time of Muhammad, who was sent to enlighten all people's intellectual and spiritual horizons: We have sent you (Muhammad) as a witness and a bearer of good tidings and a warner (48:8).
Prophet Muhammad is mentioned in the Qur'an as "the Prophet". The use of the definite article distinguishes him from all other Prophets and indicates that he is the Prophet par excellence. He has been sent as a blessing all creation, including animals, plants, and inanimate things.
God directly addresses Muhammad in many Qur'anic verses and says: We have sent you... This means that he is the Prophet sent by God to bear witness to His Existence and Unity. He carried out this task during a time of ignorance, when almost everyone denied this truth. Gradually, his followers increased until they became the global flag bearers of this truth. Prophet Muhammad conveyed the good news of happiness in this world and the next for those who do good, and warnings for those who do evil. In so doing, he performed jihad.
God has sent a Prophet to each people, which means that everyone has some idea of Prophethood. As the term used to describe the activity of Prophethood, jihad is so deeply engraved on the heart of every believer that they all feel a profound responsibility to spread the truth and thereby guide others to the Straight Path.
The lesser jihad, usually understood as fighting for God's cause, does not refer only to actual fighting on the battlefield. Rather it is comprehensive, for it includes every action from speaking out to actual fighting, provided that the action is done for the sake of God. Every individual or communal action, no matter how great or small, taken to benefit humanity is included in the meaning of the lesser jihad.
While the lesser jihad depends on mobilizing all material facilities and is performed in the outer world, the greater jihad is our personal fight against our carnal selves. These two forms of jihad cannot be separated from each other, for only those who conquer their carnal selves can perform the lesser jihad, which, in turn helps us succeed in the greater jihad.
The Messenger taught us how to perform both types of jihad, and established the principles of preaching the truth that we are to follow until the Day of Judgment. His method of acting was very systematic. This is actually another proof of his Prophethood, and a wonderful example of following the way of God in behavior.
The Messenger used to pray at the Ka'ba during the first years of his Prophethood. In addition to hoping for increased rewards from God for doing so, his foremost intention was to preach the truth to young people. But it was impossible to approach them because of their haughtiness. Knowing that actions speak louder than words, he started praying at the Ka'ba. With their curiosity aroused, they asked him what he was doing and so gave him a good opportunity to preach to them.
The Prophet was attacked several times while praying. Once, Abu Jahl planned to kill him with a big stone during his prostration. Abu Jahl held the stone aloft, ready to bring it down on the Prophet, but then began to tremble, grew pale with fear, and held his hands motionless above his head. When asked what had happened, he answered that an awful monster had come between him and the Prophet, and that it almost swallowed him. 
On another occasion when the Prophet was praying, 'Uqba ibn Abi Mu'ait wound his turban round the Prophet's neck in an attempt to strangle him. On hearing of this, Abu Bakr hurried to the scene to save the Prophet and shouted: "Would you kill a man merely because he says: 'My Lord is God'?" This was an echo of the words spoken in the time of Moses by a believer who had hurried to save him from those who wished to kill him.
The Prophet might have been martyred in any of those assaults if God had not protected him. He publicly demonstrated the importance of preaching the truth even at the risk of one's life. Abu Bakr used to recite the Qur'an loudly by the window of his house. Those who heard him started to gather around him. His recitation attracted so many people that the Makkan chiefs warned him to stop. Ibn Daghinnah, who had extended his protection to Abu Bakr, was forced to revoke it. However, Abu Bakr was determined to continue his recitation. 
Whether by words or actions, the Companions never stopped performing jihad, because they believed firmly that their personal and communal integrity depended on their active participation in jihad. Furthermore, they understood that a Muslim can secure the protection of God only by supporting His religion: Believers: if you help (the religion of) God, God will help you and make you strong (47:7). In other words, Muslims who seek protection from going astray must make struggling in the cause of God their sole goal in life.
To understand how this is done, recall how the Prophet and his Companions conducted themselves. When conditions became unbearable, some Muslims were allowed to migrate to Abyssinia. This migration was a kind of jihad to be carried out at that time. After a second migration, all Muslims who remained or had returned to Makka then emigrated to Madina.
There, the foundations were laid for both the first Islamic city-state and a new kind of jihad, one that had to take existing realities into account. Sometimes the Muslims would run and at other times they would go slowly. In other words, jihad needs its own strategy. The Muslims did not retaliate against their tormenters until God gave them permission to do so by revealing the following verse in Madina:
Permission (to take up arms) is hereby given to those who are attacked because they have been wronged; and God is able to give them victory. They are those who have been driven from their homes unjustly only because they said: "Our Lord is God." Had it not been for God's repelling some men by means of others, cloisters and churches and oratories and mosques wherein the name of God is often mentioned, would have been pulled down. God helps one who helps His religion. God is Powerful, Mighty (22:39–40).
 Bukhari, Kafala, 4.
Having borne persecution of every kind for years, the believers responded with enthusiasm. Only the Hypocrites refused to present themselves when the Prophet summoned the Muslims to fight the Makkans. The Hypocrites either sat idly in their homes or fled the battlefield, for they were slaves to their carnal selves and base desires. By contrast, all sincere Muslims hastened the battlefield whenever they were summoned to fight, for jihad was the means of reaching God and eternity. Therefore, they were as enthusiastic in their response as if they had been invited to Heaven.
Everyone considers death disagreeable, and some of the Companions were no exception. As we read in the Qur'an: Fighting is ordained for you, though it is hateful unto you. But it may happen that you dislike a thing although it is good for you and it may happen that you love a thing although it is bad for you. God knows; you do not know (2:216). Such dislike is a natural human characteristic. But the Muslims never actually disobeyed God and His Messenger, and in return God granted them success and victory. These victories gave the believers new strength and energy and, while attractive to the neighboring tribes, caused the Makkans great distress.
The Muslims kept their belief vigorous and active by means of jihad. Those who abandon jihad gradually become hopeless pessimists, for they have deprived themselves of the spirit and stop preaching the truth. Those who persevere in jihad never lose their enthusiasm and always try to increase the scope of their activities. Since every good deed results in a new one, Muslims are never deprived of good: As for those who strive for us, We guide them to our path. God is with the good (29:69).
There are as many paths leading to the Straight Path as there are numbers of breaths drawn in creation. Whoever strives for His cause is guided by God to one of these paths, and is thereby saved from going astray. Whoever is so guided lives a balanced life, neither exceeding the limits in their human needs and activities nor in their worship and other religious observances. Such balance is the sign of true guidance.
However great the sacrifices made in fighting unbelievers, they nevertheless all constitute the lesser jihad. This aspect of jihad is lesser only when compared to the greater jihad. The lesser jihad should never be underrated, for it enables Muslims to acquire the of holy warrior of Islam or the rank of martyr. Such titles open the gates to Paradise and secure God's approval.
The lesser jihad consists of striving to discharge religious obligations as perfectly as possible, whereas the greater jihad requires us to fight against our destructive drives and impulses, such as arrogance, vindictiveness, jealousy, selfishness, self-conceit, and all carnal desires.
Those who abandon the lesser jihad are liable to spiritual deterioration, due to their vulnerability to worldly weaknesses. But they can recover. Pride and love of comfort and ease may captivate Muslim soldiers returning from a victorious battle, for they may think that now it is time to relax and indulge in such things. To fight this tendency, the Prophet warned us through his Companions. Once, when returning to Madina after a victory, he said: "We are returning from the lesser jihad to the greater jihad." 
The Companions were as fierce as lions on the battlefield, and as sincere and humble as dervishes in worshipping God on the other. They used to spend most of the night praying to God. Once when night fell during a battle, two of them took turns standing guard. One rested while the other prayed. Becoming aware of the situation, the enemy shot many arrows at him. He was hit and bled profusely, but continued to pray. When he finished, he woke his friend, who asked in amazement why he had not woken him sooner. His reply was: "I was reciting Surat al-Kahf and did not wish to interrupt the deep pleasure I found therein." 
The Companions went into a trance-like state of ecstasy when in prayer, and would recite the Qur'an as if it were being revealed directly to them. Thus they never felt the pain caused by arrows hitting their bodies. Jihad, in its lesser and greater aspects, found complete expression in them.
The Prophet combined these two aspects of jihad in the most perfect way. He displayed monumental courage on the battlefield. 'Ali, one of the most courageous Muslims, admits that the Companions took shelter behind the Prophet at the most critical moments of the fighting. Once when the Muslim army experienced a reverse and began to scatter in the first phase of the Battle of Hunain, the Prophet urged his horse toward the enemy lines and shouted to his retreating soldiers: "I am a Prophet, I do not lie! I am the grandson of 'Abd al-Muttalib, I do not lie!" 
He was just as devoted when it came to worshipping God. He was consumed with love and fear of God in his prayer, and those who saw him felt great tenderness toward him. He frequently fasted successive days. Sometimes he would spend the whole night in prayer, which would cause his feet to swell. Once when 'A'isha thought his persistence in prayer was excessive, she asked him why he exhausted himself so much considering that all his sins had been forgiven. "Shall I not be a slave grateful to God?" was his only reply. 
The Prophet was so courageous that when several Makkans came near enough to discover him and Abu Bakr while they were taking shelter in the cave of Thawr, he simply said: "Don't fear; certainly God is with us." On the other hand, he was so tenderhearted that he wept profusely when reciting or listening to the Qur'an. He once requested Ibn Mas'ud to recite a passage. The latter excused himself, saying he could not recite to the one to whom the Qur'an was being revealed. But the Messenger insisted, saying that he enjoyed listening to someone else recite the Qur'an. Ibn Mas'ud then began to recite the Surat al-Nisa'. When he reached: But how will it be with them when We bring of every people a witness, and We bring you (O Muhammad) a witness against these? (4:41), the Prophet asked him to stop because, for fear of God, he could no longer bear it. Ibn Mas'ud narrates the rest of the story: "The Messenger was shedding tears so profusely that I stopped reciting."
The Prophet was as tenderhearted as he was courageous. He asked forgiveness from God at least 70 times a day, and repeatedly urged upon his community the need for asking forgiveness from God.
Those who succeed in the greater jihad are almost certain to succeed in the lesser jihad, but the reverse is not true. 'A'isha narrates: "One night the Messenger asked my permission to perform his supererogatory midnight prayer. I said: 'However much I wish for your company, I wish still more to do what you wish.' Then he performed his ablution (wudu') and began to pray. He recited: In the creation of Heavens and the Earth and (in) the alternation of night and day are tokens (of His sovereignty) for people of understanding [3:190] over and over again, shedding tears until daybreak." 
 Ibn Hanbal, Musnad, 3:344, 359.
 Bukhari, Jihad, 52, 61, 67.
 Bukhari, Tahajjud, 6.
 Bukhari, Fada'il al-Qur'an, 32, 33, 35.
Sometimes he got up to pray without wakening his wife, since he did not want to disturb her sleep. 'A'isha narrates:
One night I woke up to find the Messenger was not there. Thinking that he might be visiting another of his wives, I became very jealous. I started to get up, when my hand touched his feet in the darkness. He was prostrating and saying in his prayer: "O God, I seek refuge in Your pleasure from Your wrath, I seek refuge in Your forgiveness from Your punishment. O God, I seek refuge with You from You, I seek refuge in Your grace from Your torment, in Your mercy from Your majesty, and in Your Compassion from Your irresistible power. I am not able to praise You as You praise Yourself."
Being well aware of the obligation to follow his every action, his Companions did their best to be worthy of his company in the Hereafter. Some became physically distressed at the thought of being parted from him in the next life. For example, Thawban lost his appetite after he was unable to participate in a military expedition. On the Prophet's return, everyone went out to meet him. Thawban was so pale that the Messenger asked about his health. Thawban replied:
O Messenger, I am obsessed with fear of being parted from you in the Hereafter. You are the Messenger, so you will enter Paradise, but I don't know whether I shall deserve it. And even if God admits me, your abode certainly will be very much above mine. In this case, I shall not be able to be in your company forever. I don't know how I will be able to bear this, seeing that I cannot endure 3 days' separation from you in this world.
Thawban's worries were relieved when the Messenger told him: "You will always be in the company of the one whom you love." To love someone means to follow his or her example in this life, and the Companions were more attentive to this than any other people.
'Umar was very eager to establish a family relationship with the Messenger, for he had heard the latter say that all genealogical connections would be useless in the Hereafter, except for those with his own household. Although the Prophet held 'Umar's hand many times and said: "We will be this (like the two hands together) in the Hereafter too," 'Umar still desired the family connection. He attempted to achieve this by marrying Fatima, but she would only marry 'Ali. He married his daughter Hafsa to the Prophet and, in the later years of his caliphate, married 'Ali's daughter Umm Kulthum. If he had wished, he could have married a neighboring emperor's daughter. But his desire was to be allied to the Prophet's household.
Once Hafsa said to 'Umar: My dear father, from time to time foreign envoys come and you receive embassies. You should change your garment for a new one. 'Umar was shocked by this suggestion and replied: "How can I endure to part company with my two friends, the Prophet and Abu Bakr? I must follow their example so strictly that I can be with them in the Hereafter."
The Messenger and his Companions succeeded in the greater jihad, and their devotion to God was very strong. They spent so much of their time praying that those who saw them thought they did nothing else. But this was not the case, for they led thoroughly balanced lives.
They were very sincere in their deeds, since they did everything for the sake of God and constantly disciplined themselves. Once when 'Umar was giving a sermon, he suddenly said without any apparent reason: "O 'Umar, you were a shepherd pasturing your father's sheep." When asked after the prayer why he had said this, he answered: "It came to my mind that I was the caliph, so I became afraid of feeling proud." One day he was seen carrying a sack upon his back. When asked why he was doing this, he replied: "I felt some pride within me, so I desired to get rid of it." A later caliph, 'Umar Ibn 'Abd al-'Aziz, once wrote a letter to a friend and then tore it up. When asked why, he explained: "I prided myself on its eloquence, so I have torn it up."
Only jihad performed by such perfect souls produces effective results. Those who have not abandoned pride, self-regard, and insincerity most probably will damage the cause of Islam greatly. I would like to emphasize that such people will never obtain the desired result.
Some Qur'anic verses or chapters describe both types of jihad. One of them is: When the help of God comes, and victory, and you see men entering God's religion in throngs, then glorify the praise of your Lord, and seek His forgiveness; for He is Relenting, Merciful (110:1–3). When the believers performed the lesser jihad, whether by fighting, preaching, or enjoining the right and forbidding the wrong, God's help and victory came, and people began to enter Islam in throngs. At that moment, the All-Mighty decreed that His praises should be glorified and His forgiveness should be sought. As all success and victory are from God, it is He who must be praised and worshipped.
If we can combine our triumph over the enemy with our triumph over our carnal selves, we will have performed jihad completely. 'A'isha narrates that after the revelation of these verses, the Messenger often recited this prayer: "I glorify You with praise, O God. I seek Your forgiveness, and I turn in repentance to You." 
The Prophet expresses these two aspects of jihad together in one of his sayings: "The eyes of two persons will never witness Hellfire: the eyes of the soldier who guards the frontier and on the battlefield, and the eyes of those who shed tears for fear of God."  The first person is engaged in the lesser jihad; the latter is engaged in the greater jihad. Those who succeed in their jihad will escape the torment of Hell.
We must consider jihad in its entirety. Those who say one thing and then do another cause nothing but trouble in the ranks of Muslims. Since they cannot discipline themselves and overcome self-regard, ostentation, and the desire to dominate, they bring only disharmony to the cause of Islam. On the other hand, those who live in almost total seclusion and try to attain some high spiritual station without working to promote the truth merely reduce Islam to a "spiritual" system, like certain aspects of yoga. Such people argue that a Muslim's foremost duty is to acquire spiritual maturity so as to be saved from Hell. What they fail to realize is that those who regard themselves as safe from Hell are deceived, for God decrees that we should continue to serve Him as long as we live: And serve your Lord till the inevitable (death) comes unto you (15:99).
Muslims should never regard themselves as safe from the torments of Hell or give up hope of God's grace and forgiveness. They should tremble with fear of God, as 'Umar did. However, this fear should not prevent them from hoping to enter Paradise: But for those who fear the standing before their Lord there are two Gardens (55:46).
In short, jihad consists of self-control and preaching the truth. It requires overcoming one's carnal desires and encouraging others to do the same. Neglecting the former produces social anarchy, while neglecting the latter results in laziness. Today we must achieve a true understanding of Islam in general, and of jihad in particular. This can be realized only through strictly following the Prophet's Sunna.
 Tirmidhi, Fada'il al-Sahaba, Jihad, 12.