Except those who join a group between whom and you there is a treaty, or who come to you with their hearts feeling discomfort in fighting either against you or against their own people. If Allah had so willed, He would have given them power over you, then they would have fought you - so, if they stay away from you, and do not fight you and offer you peace, then Allah has not given you any authority against them.

It is not for a believer (Muslim) to kill any believer, except by mistake. Whoever kills a believer by mistake, then, a believing slave has to be freed, and the blood money must be paid to his family, unless they forgo it.If he (the victim) belongs to a people hostile to you and is a believer, then, a believing slave has to be freed. If he (the victim) belongs to a people between whom and you there is treaty, then, blood money is to be paid to his family, and a believing slave to be freed. Whoever does not find one has to fast for two consecutive months. This is repentance prescribed from Allah’s side. Allah is All-Knowing, All-Wise.