“Basil the Great gives us a clear understanding of the Sacred Apostolic Tradition: “Of the dogmas and sermons preserved in the Church, certain ones we have from written instruction, and certain ones we have received from the Apostolic Tradition, handed down in secret. Both the one and the other have one and the same authority for piety, and no one who is even the least informed in the decrees of the Church will contradict this. For if we dare to overthrow the unwritten customs as if they did not have great importance, we shall thereby imperceptively do harm to the Gospel in its most important points. And even more, we shall be left with the empty name of the Apostolic preaching without content. For example, let us especially make note of the first and commonest thing: that those who hope in the name of our Lord Jesus Christ should sign themselves with the sign of the Cross. Who taught this in Scripture? Which Scripture instructed us that we should turn to the east in prayer? Which of the saints left us in written form the words of invocation during the transformation of the bread of the Eucharist and the Chalice of blessing? For we are not satisfied with the words which are mentioned in the Epistles or the Gospels, but both before them and after them we pronounce others also as having great authority for the Mystery, having received them from the unwritten teaching. By what Scripture, likewise, do we bless the water of Baptism and the oil of anointing and, indeed, the one being baptized himself? Is this not the silent and secret tradition? And what more? What written word has taught us this anointing with oil itself?15 Where is the triple immersion and all the rest that has to do with Baptism, the renunciation of Satan and his angels to be found? What Scripture are these taken from? Is it not from this unpublished and unspoken teaching which our Fathers have preserved in a silence inaccessible to curiosity and scrutiny, because they were thoroughly instructed to preserve in silence the sanctity of the Mysteries? For what propriety would there be to proclaim in writing a teaching concerning that which it is not allowed for the unbaptized even to behold?” (On the Holy Spirit, chap. 27).”