I think the Divine Office, in the form of “Christian Prayer” is quite similar to the prayer book.. Mostly the same structure, same psalms. I wonder if he was talking about some of the specific prayers or..
BTW, speaking of Knox, I recommend the book “Second Friends” to anyone who hasn’t read it...
No, he was talking about the Book of Common Prayer, originally the work of Archbishop Cranmer, a heretic but a master of the language. People may sentimentalize about the Latin mass, but most low masses were pretty dreary affairs. He knew he had got the better part, but he still felt the loss. He was, I think, the son of a bishop.