"Prophets or Doctors are the interpreters of the revelation; they unfold and define its mysteries, they illuminate its documents, they harmonize its contents, they apply its promises. Their teaching is a vast system, not to be comprised in a few sentences, not to be embodied in one code or treatise, but consisting of a certain body of Truth, pervading the Church like an atmosphere, irregular in its shape from its very profusion and exuberance; at times separable only in idea from Episcopal Tradition, yet at times melting away into legend and fable; partly written, partly unwritten, partly the interpretation, partly the supplement of Scripture, partly preserved in intellectual expressions, partly latent in the spirit and temper of Christians; poured to and fro in closets and upon the housetops, in liturgies, in controversial works, in obscure fragments, in sermons, in popular prejudices, in local customs. This I call Prophetical Tradition, existing primarily in the bosom of the Church itself, and recorded in such measure as Providence has determined in the writings of eminent men. Keep that which is committed to thy charge, is St. Paul's injunction to Timothy; and for this reason, because from its vastness and indefiniteness it is especially exposed to corruption, if the Church fails in vigilance. This is that body of teaching which is offered to all Christians even at the present day, though in various forms and measures of truth, in different parts of Christendom, partly being a comment, partly an addition upon the articles of the Creed."[77:1] If this be true, certainly some rule is necessary for arranging and authenticating these various expressions and results of Christian doctrine. No one will maintain that all points of belief are of equal importance. "There are what may be called minor points, which we may hold to be true without imposing them as necessary;" "there are greater truths and lesser truths, points which it is necessary, and points which it is pious to believe."[77:2] The simple question is, How are we to discriminate the greater from the less, the true from the false. 3.