What is the ruling of the Shari'ah on a man who does not spend on his third wife and her children despite his comfortable financial situation, and prefers to spend on his first wife? And does she have a right to the deferred dowry? And what should she do to restore her rights?

A man must fear Allah regarding his wife and give her her full, undiminished dowry if its time is due and he is able to pay it, as Allah Almighty says: "And give women their dowries with a good heart." And he is not allowed to delay it after it becomes due if he is able to pay it, as the Prophet, peace and blessings be upon him, said: "The delay of a rich person is oppression." And whatever part of her right he has not paid is a debt upon him.

He is also obligated to spend on his wife and his poor children, for they are a trust upon him about which he will be questioned on the Day of Resurrection, as the Prophet, peace and blessings be upon him, said: "All of you are guardians, and all of you are responsible for your charges," and "It is enough sin for a man to neglect those whom he supports."

He must also know that polygyny is permitted for whoever is able to be just and practices it, as Allah Almighty says: "But if you fear that you will not be just, then [marry only] one." And whoever is not just will come on the Day of Resurrection with half of his body drooping.