documents took concrete and logical shape under stress of successive controversies forced upon her for several generations to come. So her beliefs became clear-cut and, in a manner, stereotyped. Vagueness disappeared; and she acquired a nucleus of guiding principles which should never grow obsolete, though their application and temporary expression might vary from age to age. As specimens of the good that can come out of error, it will be enough to point out that we owe to the Colossian heresy the