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Offensive Jihad (where the enemy is attacked in his own territory).
Where the Kuffar are not gathering to fight the Muslims. The fighting becomes Fard Kifaya with the minimum requirement of appointing believers to guard borders, and the sending of an army at least once a year to terrorise the enemies of Allah. It is a duty of the Imam to assemble and send out an army unit into the land of war once or twice every year. Moreover, it is the responsibility of the Muslim population to assist him, and if he does not send an army he is in sin.- And the Ulama have mentioned that this type of jihad is for maintaining the payment of Jizya. The scholars of the principles of religion have also said: " Jihad is Daw'ah with a force, and is obligatory to perform with all available capabilities, until there remains only Muslims or people who submit to Islam."
Defensive Jihad
This is expelling the Kuffar from our land, and it is Fard Ayn, a compulsory duty upon all. It is the most important of all the compulsory duties and arises in the following conditions:
1) If the Kuffar enter a land of the Muslims.
2) If the rows meet in battle and they begin to approach each other.
3) If the Imam calls a person or a people to march forward then they must march.
4) If the Kuffar capture and imprison a group of Muslims.
The First Condition: With reference to the Kuffar entering a land of the Muslims.
In this Condition the pious predecessors, those who succeeded them, the Ulama of the four Mathhabs (Maliki, Hanafi, Shaffie and Hanbali), the Muhadditheen, and the Tafseer commentators, are agreed that in all Islamic ages, Jihad under this condition becomes Fard Ayn upon the Muslims of the land which the Kuffar have attacked and upon the Muslims close by, where the children will march forth without the permission of the parents, the wife without the permission ofher husband and the debtor without the permission of the creditor. And, if the Muslims of this land cannot expel the Kuffar because of lack of forces, because they slacken, are indolent or simply do not act, then the Fard Ayn obligation spreads in the shape of a circle from the nearest to the next nearest. If they too slacken or there is again a shortage of manpower, then it is upon the people behind them, and on the people behind them, to march forward. This process continues until it becomes Fard Ayn upon the whole world.
Sheikh Ibn Taymia says on this topic: "About the defensive jihad, which is repelling an aggressor, is the most tasking type of jihad. As agreed upon by everyone, it is obligatory to protect the religion and what is sacred. The fIrst obligation after Iman is the repulsion of the enemy aggressor who assaults the religion and the worldly affairs. There are no conditional requirements such as supplies or transport, rather he is fought with all immediate capability .The Ulama, our peers and others have spoken about this." Ibn Taymia supports his opinion of the absence of the requirement of transport in his reply to the judge who said: "If jihad becomes Fard Ayn upon the people ofa country, one of the requirements, in comparison to Hajj, is that one must have supplies and a ride if the distance is such that one shortens the prayer". Ibn Taymia said: "What the Judge has said in comparison to Hajj has not been stated before by anybody and is a weak argument. Jihad is obligatory because it is for the repulsion of the harm of the enemy, therefore it has priority over Hijr. For Hijr no transport is considered necessary. Of the jihads some take priority." It is furthered in a sahih hadith narrated by Ebaad Bin Asaamat that the Prophet (saw) said: "it is upon the Muslim to listen and obey in hardship and prosperity , in what he likes and dislikes, and even if he is not given his rights". Therefore, the pillar of the most important of obligations, is the marching forward in times of hardship as well as prosperity. As has been stated, contrary to Hajj, the obligation remains present in times of hardship. And this is in offensive jihad. So it is clear that defensive jihad carries a greater degree of obligation. To defend the sacred things and the religion from the aggressor is obligatory , as agreed upon by everyone. "The fIrst obligation after Iman is repulsion of the enemy aggressor who assaults the religion and the worldly affairs." Now we look at the opinions of the four Mathhabs who are all in agreement on this point.
Kafir (Arabic: كافر kāfir; plural كفّار kuffār) is an Arabic word meaning an unbeliever, a person who hides, denies, or covers the truth. In cultural terms, it is a derogatory term[1] used to describe an unbeliever, non-Muslims, a Muslim of a differing sect, or an apostate from Islam. It is usually translated into English as "infidel" or "unbeliever."