Russia and the BCP

I. There is nothing in the actual contents of “Daily Morning and Evening Prayer,” together with the collects, which change according to the season, which is open to any particular objection on the positive side from the Orthodox point of view, unless the addition of the Filioque to the Creed is taken into account. But at the same time, while the recourse in prayer to the Most Holy Mother of God, to the Angel Hosts, and to the illustrious saints, the glorification and invocation of them, forms an essential part of Orthodox and Catholic worship, these things are entirely foreign to Anglican worship. It is absolutely necessary that there should be introduced into this worship some such prayers (or hymns) in one or another form and degree.

Russian Observations upon the American Prayer Book