A letter sent to a friend containing some reflections upon a late book intituled, The Roman church vindicated, and M.S. convicted of a false witnesse against her : Wherein is declar'd, that the Pope may excommunicate and depose Kings according to the judgement of their greatest doctors, decrees and practices of several Popes, and Canons of their most approved councils; and the author convicted of most notorious falsities, &c. By J.S. B.D.