Vincent of Lérins’s rule that “Christianity is what has been held always, everywhere, and by all,” cannot suffice to delineate the content of Christian faith today.22 By admitting this, Newman is not arguing that the doctrine of the Trinity represents a rupture with the pre-Nicene Church; rather, in light of Anglican efforts to invoke the Vincentian canon as the measure of sound doctrine, he is arguing that if we are wary of accepting any doctrine that historians cannot show to have been accepted by the earliest Church, then we will also have to be wary of accepting the doctrine of the Trinity.23 The attempt to do without the Church, and to hold only that which the Bible explicitly teaches, does not work either, not least because the Bible does not present itself as a source to be interpreted without the Church.24 The meaning of Scripture’s words cannot be known without interpretation, which involves more than the mere repetition of Scripture’s words.25 A living ecclesial authority is necessary.