Why does Mrs. Dolly Winthrop insist that Marner must take the child to church?

From the text:

“No, to be sure; you’ll have a right to her, if you’re a father to her, and bring her up according. But,” added Dolly, coming to a point which she had determined beforehand to touch upon, “you must bring her up like christened folks’s children, and take her to church, and let her learn her catechise, as my little Aaron can say off—the “I believe”, and everything, and “hurt nobody by word or deed”,—as well as if he was the clerk. That’s what you must do, Master Marner, if you’d do the right thing by the orphin child.”