Hi Haruo, the explanation for cod as given above is correct its an old english theatrical term for a piece of fakery.
Joe, I think that what you have above is just about it. Its part of a long monologue Henry does about his childhood with a whole raft of character impersonations. In this instance he is recounting his memories as an altar boy in an evangelical church which had this elderly lady given to making up spirituals on the spot hence the reeboks example. I don't think it is meant to scan and should be rendered in a high quavery voice to the tune of Amazing Grace.