Salam wa alykoum, I am emailing you to ask you what islam say about my kids live with their christian mother as we are divorced? and now she is has a boy friend, she is a good woman as she respected me and she never bring her boyfriend to her house while my kids there with her, but is that right i stop her bring her partner to her house while my kids there, he partner is christian as well.. I really need your advice what islam order me regarding to this issue. my kids are muslims hamdollah and i have 2 boys age 9 and 5 years, and one daughter age is 7 salam wa alykoum

All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad, sallallaahu ‘alayhi wa sallam, is His Slave and Messenger.

You should know that one of the conditions of custody is that the person who takes custody is a Muslim, according to the preponderant opinion of the jurists and thus your non-Muslim wife has no right to the custody of those children. Hence, you have to explore every possible avenue to take them from her and not to enable her regarding their custody. The matter is very dangerous because she may corrupt their beliefs and morals either through her direct  instructions or through getting accustomed to seeing her false rituals and erroneous conduct.

If you could not get their custody, you should apply the basic rule that states that what is possible is not to be omitted because of what is not possible. Accordingly, strive hard to lessen the risks and corruption. Amongst the forms of that is to prevent her, if that is possible and will cause no greater harm, from bringing her boyfriend to her house when your children are present, to ward off evil from them. In all cases, you have to keep close touch with your children and take good care of them in this stage until they reach the age in which they can be independent from their mother.

It is worth mentioning here that what you have stated is only one of so many evils and dangers caused by marrying a non-Muslim woman.

To get more benefit, kindly refer to Fataawa 81957, 144277 and 198609.

Allaah Knows best.