The penalties that the Sharee'ah has introduced for those who disobey Allah and His Messengers are of two kinds:

1) The punishment of those who are under the sway [of the Imam], both individuals and collectivities, as has been mentioned before [in the chapter on criminal law], and;

2) The punishment of recalcitrant groups, such as those that can only be brought under the sway of the Imam by a decisive fight.

That then is the jihad against the unbelievers (kufaar), the enemies of Allah and His Messenger. For whoever has heard the summons of the Messenger of Allah, (salallaahu 'alayhee wa sallam), and has not responded to it, must be fought, "until there is no persecution and the religion is Allah’s entirely." [Qur'an., 2:193, 8:39]

When Allah sent His Prophet (salallaahu 'alayhee wa sallam) and ordered him to summon the people to His religion, He did not permit him to kill or fight anyone for that reason before the Prophet (salallaahu 'alayhee wa sallam) emigrated to Medina.

Thereafter, He gave him and the Muslims permission with the words:

"Leave is given to those who are fought because they were wronged - surely Allah is able to help them - who were expelled from their habitations without right, except that they say ‘Our Lord is Allah.’ Had Allah not driven back the people, some by the means of others, there would had been destroyed cloisters and churches, oratories and masjids, wherein Allah’s name is much mentioned. Assuredly Allah will help him who helps Him - surely Allah is all-strong, all-mighty - who, if We establish them in the land, perform the prayer, and pay the alms, and bid to honour, and forbid dishonour; and unto Allah belongs the issue of all affairs." [Qur'an., 22:39-41]

"Prescribed for you is fighting, though it be hateful to you. Yet it may happen that you will hate a thing which is better for you; and it may happen that you love a thing which is worse for you. Allah knows and you know not." [Qur'an., 2:216]

"Say: ‘If your fathers, your sons, your brothers, your wives, your clan, your possessions that you have gained, commerce you fear may slacken, dwellings you love - if these are dearer to you than Allah and His Messenger, and to struggle in His way, then wait till Allah brings His command; Allah guides not the people of the ungodly.’" [Qur'an., 9:24]

"The believers are those who believe in Allah and His Messenger, then have not doubted, and have struggled with their possessions and their selves in the way of Allah; those - they are the truthful ones." [Qur'an., 49:15]

"Then, when a clear sura is sent down, and therein fighting is mentioned, thou seest those in whose heart is sickness looking at thee as one who swoons of death; but better for them would be obedience and words honourable. Then when the matter is resolved, if they were true to Allah, it would be better for them." [Qur'an., 47:20-21]

"O believers, shall I direct you to a commerce that shall deliver you from a painful chastisement? You shall believe in Allah and His Messenger, and struggle in the way of Allah with your possessions and your selves. That is better for you, did you but know. He will forgive you your sins and admit you into gardens underneath which rivers flow, and to dwelling places goodly in Gardens of Eden; that is the mighty triumph; and other things you love, help from Allah and a nigh victory. Give thou good tidings to the believers." [Qur'an., 61:10-13]

"Do you reckon the giving of water to pilgrims and the inhabiting of the Holy Masjid as the same as one who believes in Allah and the Last Day and struggles in the way of Allah? Not equal are they in Allah’s sight; and Allah guides not the people of the evildoers. Those who believe, and have emigrated, and have struggled in the way of Allah with their possessions and their selves are mightier in rank with Allah; and those - they are the triumphant; their Lord gives them good tidings of mercy from Him and good pleasure; for them await gardens wherein is lasting bliss, therein to dwell forever and ever; surely with Allah is a mighty wage." [Qur'an., 9:19-21]

"O believers, whosoever of you turns from his religion, Allah will assuredly bring a people He loves, and who love Him, humble towards the believers, disdainful towards the unbelievers, men who struggle in the path of Allah, not fearing the reproach of any reproacher. That is Allah’s bounty; He gives it unto whom He will." [Qur'an., 5:54]

"That is because they are smitten neither by thirst, nor fatigue, nor emptiness in the way of Allah, neither tread they any tread enraging the unbelievers, nor gain any gain from any enemy, but a righteous deed is thereby written to their account; Allah leaves not to waste the wage of the good-doers. Nor do they expend any sum, small or great, nor do they traverse any valley, but it is written to their account, that Allah may recompense them the best of what they were doing."
[Qur'an., 9:120-121]

The command to participate in jihad and the mention of its merits occur innumerable times in the Qur'an and the Sunnah.

Therefore it is the best voluntary [religious] act that man can perform. All scholars agree that it is better than the hajj (greater pilgrimage) and the 'umrah (lesser pilgrimage), than voluntary salaat and voluntary fasting, as the Qur'an and the Sunnah indicate.

The Prophet, (salallaahu 'alayhee wa sallam) has said:
 

And he (salallaahu 'alayhee wa sallam) has said:
 

Al-Bukhaari has transmitted that he (salallaahu 'alayhee wa sallam) has said:
 

And, as related by Muslim, he (salallaahu 'alayhee wa sallam) has said:
 

It is related in the Sunan that:
 

He (salallaahu 'alayhee wa sallam) has said,
 

Al-Tirmidhi has said about this tradition that it is good (hasan). In the Musnad of Ahmad ibn Hanbal we find:
 

In the Saheeh of al-Bukhaari as well as the Saheeh of Muslim we find:
 

In the Sunan we find that Muhammed, (salallaahu 'alayhee wa sallam) has said:
 

This is a vast subject, unequalled by other subjects as far as the reward and merit of human deeds is concerned. This is evident upon closer examination. The [first] reason is that the benefit of jihad is general, extending not only to the person who participates in it but also to others, both in a religious and a temporal sense.

[Secondly,] jihad implies all kinds of worship, both in its inner and outer forms. More than any other act it implies love and devotion for Allah, Who is exalted, trust in Him, the surrender of one’s life and property to Him, patience, asceticism, remembrance of Allah and all kinds of other acts [of worship]. And the individual or community that participates in it, finds itself between two blissful outcomes: either victory and triumph or martyrdom and Paradise.

[Thirdly,] all creatures must live and die. Now, it is in jihad that one can live and die in ultimate happiness, both in this world and in the Hereafter. Abandoning it means losing entirely or partially both kinds of happiness. There are people who want to perform religious and temporal deeds full of hardship in spite of their lack of benefit, whereas actually jihad is religiously and temporally more beneficial than any other deed full of hardship. Other people [participate in it] out of a desire to make things easy for themselves when death meets them, for the death of a martyr is easier than any other form of death.

In fact, it is the best of all manners of dying.

Since lawful warfare is essentially jihad and since its aim is that the religion is Allah’s entirely [2:189, 8:39] and Allah’s word is uppermost [9:40], therefore, according to all Muslims, those who stand in the way of this aim must be fought.

As for those who cannot offer resistance or cannot fight, such as women, children, monks, old people, the blind, handicapped and their likes, they shall not be killed, unless they actually fight with words [e.g. by propaganda] and acts [e.g. by spying or otherwise assisting in the warfare].

Some [jurists] are of the opinion that all of them may be killed, on the mere ground that they are unbelievers, but they make an exception for women and children since they constitute property for Muslims.

However, the first opinion is the correct one, because we may only fight those who fight us when we want to make Allah’s religion victorious. Allah, Who is exalted, has said in this respect:
 

In the Sunan it is reported from the Messenger of Allah, (salallaahu 'alayhee wa sallam):
 

It is also reported in the Sunan that he used to say:
 

This means that, although there is evil and abomination in killing, there is greater evil and abomination in the persecution of the unbelievers. Now, the unbelief of those who do not hinder the Muslims from establishing Allah’s religion, is only prejudicial to themselves.

In the same vein, the jurists have said that the one who propagates innovations (bid'ah) that are contrary to the Qur'an and the Sunna must be punished much more severely than the person [who holds such beliefs but] remains silent.

"A mistake that is kept secret," says a Tradition, "only harms the person who has committed it, but if it becomes public and is not denounced, it harms the community."

The Sharee'ah enjoins fighting the unbelievers, but not the killing of those who have been captured. If a male unbeliever is taken captive during warfare or otherwise, e.g. as a result of a shipwreck, or because he lost his way, or as a result of a ruse, then the head of state (imaam) may do whatever he deems appropriate: killing him, enslaving him, releasing him or setting him free for a ransom consisting in either property or people. This is the view of most jurists and it is supported by the Qur'an and the Sunna. There are, however, some jurists who hold that the options of releasing them or setting them free for a ransom have been abrogated. As for the People of the Book and the Zoroastrians (Majoos), they are to be fought until they become Muslims or pay the tribute (jizya) out of hand and have been humbled. With regard to the others, the jurists differ as to the lawfulness of taking tribute from them. Most of them regard it as unlawful of taking tribute from them. Most of them regard it as unlawful to accept it from [heathen] Arabs.

If a rebellious group, although belonging to Islam, refuses to comply with clear and universally accepted commands, all Muslims agree that jihad must be waged against them, in order that the religion will be Allah’s entirely. Thus Abu Bakr as-Siddeeq and other Sahaabah, (radiallaahu 'anhum), have fought those who refused to pay zakaat. Initially some of the Sahaabah hesitated in fighting them, but eventually they all agreed. 'Umar ibn al-Khattaab said to Abu Bakr, (radiallaahu 'anhumaa):
 

There are various authentic Traditions according to which the Prophet, (salallaahu 'alayhee wa sallam), has ordered to fight the Khawaarij. In the Saheeh of al-Bukhaari as well as the Saheeh of Muslim it is reported on the authority of 'Alee ibn Abee Taalib, (radiallaahu 'anhu), that he said:
 

Muslim has reported that 'Alee, (radiallaahu 'anhu), said:
 

In another version of this Tradition, transmitted on the authority of Abu Sa'eed from the Prophet, (salallaahu 'alayhee wa sallam), we find the following words:
 

There is unanimity about the authenticity of this tradition.

In another Tradition reported by Muslim it is said:
 

These were the people that were killed by the Ameer ul Mu'mineen (Commander of the Faithful) 'Alee, when the breach between the people of Iraq and the people of Syria took place. They were called hurooriyya. The Prophet, (salallaahu 'alayhee wa sallam), has made it clear that both parties into which the community had fallen apart, belonged to his community and that the partisans of 'Alee were closer to the truth. He incited to fight only those heretics that had abandoned Islam and had left the community and that had permitted the taking of the lives and properties of the other Muslims. It has been established on the authority of the Qur'an, the Sunna, and the Ijmaa (Consensus) of the Community, that those who depart from the law of Islam must be fought, even if they pronounce the two professions of faith.

The jurists disagree about the permissibility to fight rebellious groups that abandon an established supererogatory act of worship (sunna raatiba), such as the two [extra] rak'as of dawn prayer. There is, however, unanimity that it is allowed to fight people for [not observing] unambiguous and generally recognized obligations and prohibitions, until they undertake to perform the explicitly prescribed prayers, to pay zakaat, to fast during the month of Ramadaan, to make the pilgrimage to Makkah and to avoid what is prohibited, such a marrying women in spite of legal impediments, eating impure things, acting unlawfully against the lives and properties of Muslims and the like. It is obligatory to take the initiative in fighting those people, as soon as the Prophet’s (salallaahu 'alayhee wa sallam) summons with the reasons for which they are fought has reached them.

But if they first attack the Muslims, then fighting them is even more urgent, as we have mentioned when dealing with the fighting against rebellious and aggressive bandits.

The most serious type of obligatory jihad is the one against the unbelievers and against those who refuse to abide by certain prescriptions of the Sharee'ah, like those who refuse to pay zakaat, the Khawaarij and the like. This jihad is obligatory if it is carried out on our initiative and also if it is waged as defence. If we take the initiative, it is a collective duty (Fard Kifayah), [which means that] if it is fulfilled by a sufficient number [of Muslims], the obligation lapses for all others and the merit goes to those who have fulfilled it, just as Allah, He is exalted, has said:
 

But if the enemy wants to attack the Muslims, then repelling them becomes a duty for all those under attack and for the others to help them. Allah, He is exalted, has said:
 

In the same vein the Prophet (salallaahu 'alayhee wa sallam) has ordered Muslims to help fellow Muslims.

The assistance, which is obligatory both for the regular professional army and for others, must be given, according to everybody’s possibilities, either in person, by fighting on foot or on horseback, or through financial contributions, be they small or large. When the Muslim were attacked by the enemy in the year of the Trench, Allah did not permit anybody to abandon jihad, although He did allow them not to take part in jihad [after the siege was lifted] in order to pursue the enemy. At that occasion He divided them into two categories, those who sat at home and those who marched out, and He criticized those who were asking the Prophet (salallaahu 'alayhee wa sallam) for leave [not to take part in jihad]:
 

So the latter [form of jihad] consists in defense of the religion, of things that are inviolable, and of lives. Therefore it is fighting out of necessity. The former [type of jihad], however, is voluntary fighting in order to propagate the religion, to make it triumph and to intimidate the enemy, such as was the case with the expedition to Tabook and the like.

Now, this form of punishment [i.e. jihad] must be administered to rebellious people. As for inhabitants of the territory of Islam who are not rebellious [but refuse to carry out religious duties], they must be forced to carry out their obligations such as the five fundamental duties of Islam and others like the delivering of trusts to their owners and the preserving of covenants in social relations.

Transl. R.P.