Third Rome on First

"The Russian Church has accepted the authenticity of Roman Catholic sacraments per se (not by economia) since at least the early 17th century (Council of Moscow 1667)," says Hiermonk Ambrose, elaborating, "In other words Roman Catholics receive the true Body and Blood of Christ from the hands of their priests and the Pope of Rome is a true bishop," quoted by Serge here, who suggests that "sacramentally they’re the same church with only one real difference, the scope of the Pope, an inch wide but miles deep" — Interesting answer to the nastydox on grace in the RC Church.

More from Father Ambrose: "Moscow accepts the 15th-century Council of the Four Patriarchs (1484) on this matter and Russian canon law forbids the baptism of Catholics. This has not been annulled and it applies today."