Must a husband prevent his wife from visiting her family who drink alcohol, eat unslaughtered meat, do not pray regularly, deny some fundamental tenets of the religion, and advocate matters contrary to Islamic law, knowing that the wife is newly committed to religious observance and he fears for her from their influence?

It is permissible for the husband to prevent his wife and children from visiting relatives if he fears temptation or corruption for them, and they must obey, for Allah Almighty says: "Protect yourselves and your families from a Fire." The basic principle is that the husband should not prevent the wife's parents from visiting her, but he may prevent it if there is a definite harm resulting from it, and the rule is: "There shall be no harm or reciprocating harm." As for siblings, they take the same ruling as parents, but relatives through breastfeeding are to be prevented. The questioner must weigh the benefits against the harms; if mixing is harmful, then prevention is obligatory, but if it is beneficial without harm, then enjoining good and forbidding evil is obligatory. The husband is responsible for assessing the harm.