Impermissibility of dedicating Waqf to some children to the exclusion of others

Q: A man has a number of sons, some by his wife and others by slave women. He wants to dedicate two-thirds of his land and real estate as Waqf (endowment) for the slave women and their children and not the other sons. Is this permissible?

A: It is not permissible to make a Waqf for some sons and not others, as this Waqf will be unjust and it was declared Haram (prohibited) by the Prophet (peace be upon him) who said, “Fear Allah and treat your children fairly.” (Agreed upon by Al-Bukhari and Muslim) May Allah grant us success. May peace and blessings be upon our Prophet Muhammad, his family, and Companions.