For want of a preposition, the kingdom is obscured.
I don't care if you pray to me or not, Mrs. D. It has no bearing on anything in my life, but it does negatively impact yours. And I wouldn't want to encourage that kind of error. I have no power over you regarding your salvation. Nor does Mary nor anyone else.
Pray to God for me, if you are so moved, and I'm happy to return the favor.
That's what "I pray you, dear Dr. Eckleburg, please pray to the Lord for me, a sinner" MEANS, y'know!