POPE of Rome, The, Sylvester Hassell Also about 1150, Rome, in the codification of her canon law, went beyond even the Pseudo-Isodorian positions,—maintaining not only that the pope is the vicar of Peter, but also that Bishops are only vicars of the pope, and that all the greater or more important causes are to be brought before the papal tribunal.” (Hassell’s History pg 435)