Muhammad taking his son's wife

Call them by their fathers’ names, that is more just in the sight of Allah. But if you do not know their fathers, then they are your brothers in faith and your companions. There is no blame upon you for unintentional mistakes, but what your hearts deliberately intend.

33:5Proclaim their real parentage. That will be more equitable in the sight of Allah. And if ye know not their fathers, then (they are) your brethren in the faith, and your clients. And there is no sin for you in the mistakes that ye make unintentionally, but what your hearts purpose (that will be a sin for you). Allah is ever Forgiving, Merciful.