What is the ruling of Islamic law regarding the custody of a child, and who has a greater right to it in the event that the mother had previously dealt with sorcery before her divorce, knowing that she is pregnant in Jordan and the father is in Saudi Arabia?

If the wife is untrustworthy, she has no right to custody of the children. The maintenance of a child in need is obligatory upon the father in all cases. The Sharia judge is the one who decides disputes related to custody, so you must refer the matter to the court. If the court rules that the mother has custody, then strive to communicate with your child and raise him upon virtues.