What is the ruling on a father relinquishing a portion of his property to his two sons during his lifetime?

A father may gift his children whatever he wishes, provided he is just, which is what your father did. A gift is not owned until it is taken possession of. If the child does not take possession of the gift and the father dies, the gift becomes void and becomes part of the inheritance, to be divided among the heirs. Possession of agricultural land is achieved by working on it or renting it out, while non-agricultural land is possessed by registration and knowing its boundaries. If you have taken possession of the acres, they are yours. Otherwise, the gift was not completed, and the land becomes part of the inheritance to be divided among the heirs.