What is Dimmesdale's argument for keeping Hester and Pearl together?

Dimmesdale argues (following Hester) that since God gave Pearl to Hester, then the men do not have any right to contradict the will of God and the child should stay with the mother. But Dimmesdale might also be arguing such because he is Pearl's father, after all, and party to Hester's sin. In a way, he is covering for her.