Is the father sinful for selling the farm that was registered in his name without the consent of his son, who paid its price and invested in it, and does the son have a legitimate right to this farm?

It is not permissible for a father to take from his son's money except out of necessity. This is the view of the majority of jurists. The Hanbalis, however, permit taking without necessity, provided two conditions are met: that he does not cause hardship or harm to the son, and that he does not take in order to give it to another child. Based on this, what the father did by selling the farm and distributing its price is a clear injustice, because he took what he did not need, harmed his son, and gave his money to others. He must repent and reverse the sale if he is able; otherwise, he must return an equivalent amount of the price to his son.