[2.191] And kill them wherever you find them, and drive them out from whence they drove you out, and persecution is severer than slaughter, and do not fight with them at the Sacred Mosque until they fight with you in it, but if they do fight you, then slay them; such is the recompense of the unbelievers.
[9.12] And if they break their oaths after their agreement and (openly) revile your religion, then fight the leaders of unbelief-- surely their oaths are nothing-- so that they may desist.
[9.29] Fight those who do not believe in Allah, nor in the latter day, nor do they prohibit what Allah and His Apostle have prohibited, nor follow the religion of truth, out of those who have been given the Book, until they pay the tax in acknowledgment of superiority and they are in a state of subjection.
[22.39] Permission (to fight) is given to those upon whom war is made because they are oppressed, and most surely Allah is well able to assist them;
[48.16] Say to those of the dwellers of the desert who were left behind: You shall soon be invited (to fight) against a people possessing mighty prowess; you will fight against them until they submit; then if you obey, Allah will grant you a good reward; and if you turn back as you turned back before, He will punish you with a painful punishment.
[61.4] Surely Allah loves those who fight in His way in ranks as if they were a firm and compact wall.
[8.65] O Prophet! urge the believers to war; if there are twenty patient ones of you they shall overcome two hundred, and if there are a hundred of you they shall overcome a thousand of those who disbelieve, because they are a people who do not understand.
[3.28] Let not the believers take the unbelievers for friends rather than believers; and whoever does this, he shall have nothing of (the guardianship of) Allah, but you should guard yourselves against them, guarding carefully; and Allah makes you cautious of (retribution from) Himself; and to Allah is the eventual coming.
[4.74] Therefore let those fight in the way of Allah, who sell this world's life for the hereafter; and whoever fights in the way of Allah, then be he slain or be he victorious, We shall grant him a mighty reward.
[47.4] So when you meet in battle those who disbelieve, then smite the necks until when you have overcome them, then make (them) prisoners, and afterwards either set them free as a favor or let them ransom (themselves) until the war terminates. That (shall be so); and if Allah had pleased He would certainly have exacted what is due from them, but that He may try some of you by means of others; and (as for) those who are slain in the way of Allah, He will by no means allow their deeds to perish.
From the Holy Koran.