Jonas's father has the Assignment of Nurturer - he helps to give care to newborn children until they are assigned to a family unit. This is a good placement for him, as he is patient and gentle, loving and supportive of the babies. He is truly concerned with one child who is not progressing at the expected speed and gets special permission to bring this child to his living quarters at night.
as a result of Father's plea, Gabriel had been labeled Uncertain and given the additional year. He would continue to be nurtured at the Center and would spend his nights with Jonas's family unit.
His attempts to help Gabe, his nickname for the infant who is to be named Gabriel when/if given to a family unit, show his dedication to his work.
At the same time, part of his job is to uphold the community in all its expectations and regulations. As part of the society structure, every person is unique. When twins are born, it is part of Father's duties to make the determination of which will be nurtured for eventual raising by a famiy unit and which will be "released." He carries out the procedures involved in doing so without hesitation or thought about the deeper significance of what he is doing.
Jonas's father is a good member of the community - he is content not needing to think for himself.