How shall Allah guide a people who disbelieved after their believing and (after) they had borne witness that the Messenger was true and clear arguments had come to them; and Allah does not guide the unjust people.

O you who believe! call to witness between you when death draws nigh to one of you, at the time of making the will, two just persons from among you, or two others from among others than you, if you are travelling in the land and the calamity of death befalls you; the two (witnesses) you should detain after the prayer; then if you doubt (them), they shall both swear by Allah, (saying): We will not take for it a price, though there be a relative, and we will not hide the testimony of Allah for then certainly we should be among the sinners.