And whoever acts hostilely to the Messenger after that guidance has become manifest to him, and follows other than the way of the believers, We will turn him to that to which he has (himself) turned and make him enter hell; and it is an evil resort.

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.

And to Madyan (We sent) their brother Shu'aib. He said: O my people! serve Allah, you have no god other than Him; clear proof indeed has come to you from your Lord, therefore give full measure and weight and do not diminish to men their things, and do not make mischief in the land after its reform; this is better for you if you are believers:

And those who speak evil things of the believing men and the believing women without their having earned (it), they are guilty indeed of a false accusation and a manifest sin.