There is no compulsion in religion; truly the right way has become clearly distinct from error; therefore, whoever disbelieves in the Shaitan and believes in Allah he indeed has laid hold on the firmest handle, which shall not break off, and Allah is Hearing, Knowing.

And it does not behoove a believer to kill a believer except by mistake, and whoever kills a believer by mistake, he should free a believing slave, and blood-money should be paid to his people unless they remit it as alms; but if he be from a tribe hostile to you and he is a believer, the freeing of a believing slave (suffices), and if he is from a tribe between whom and you there is a convenant, the blood-money should be paid to his people along with the freeing of a believing slave; but he who cannot find (a slave) should fast for two months successively: a penance from Allah, and Allah is Knowing, Wise.