30 Another Saturninus of Tucca said: "The Gentiles, although they worship idols, yet acknowledge and confess the supreme God, the Father and Creator. Against Him Marcion blasphemes, and some men do not blush to approve the baptism of Marcion. How do such priests either maintain or vindicate the priesthood of God, who do not baptize the enemies of God, and hold communion with them while they are thus unbaptized?"
31. The answer is this: Truly when such terms as this are used, all moderation is passed; nor do they take into consideration that even they themselves hold communion with such men, "judging no one, nor removing any from the right of communion if he entertain a contrary opinion." But Saturninus has used an argument in this very judgment of his, which might furnish materials for his admonition (if he would pay attention to it), that in each man what is wrong should be corrected, and what is right should be approved, since he says, "The Gentiles, although they worship idols, yet acknowledge and confess the supreme God, the Father and Creator." If, then, any Gentile of such a kind should come to God, would he wish to correct and change this point in him, that he acknowledged and confessed God the Father and Creator? I trow not. But he would amend in him his idolatry, which was an evil in him; and he would give to him the sacraments of Christ, which he did not possess; and anything that was wayward which he found in him he would correct; and anything which had been wanting he would supply. So also in the Marcionist heretic he would acknowledge the perfectness of baptism, he would correct his waywardness, he would teach him Catholic truth.
Source: On Baptism, Against the Donatists (New Advent)