Why does dimmesdale argue that it would be better for pearl to stay with her mother?

Dimmesdale argues that it would be better for Pearl to stay with her mother, Hester, because he believes that Hester has the ability to provide love and care for their daughter in a way that he cannot due to his position in the community as a revered minister. He also believes that Hester's influence will help shape Pearl's character positively.