4:90Except those who join people with whom you have a treaty, or those who come to you reluctant to fight you or fight their own people. Had God willed, He would have given them power over you, and they would have fought you. If they withdraw from you, and do not fight you, and offer you peace, then God assigns no excuse for you against them.

4:92Never should a believer kill another believer, unless by error. Anyone who kills a believer by error must set free a believing slave, and pay compensation to the victim’s family, unless they remit it as charity. If the victim belonged to a people who are hostile to you, but is a believer, then the compensation is to free a believing slave. If he belonged to a people with whom you have a treaty, then compensation should be handed over to his family, and a believing slave set free. Anyone who lacks the means must fast for two consecutive months, by way of repentance to God. God is All-Knowing, Most Wise.