"Our volumes are put up for sale in public; the light never needs to blush. Let them buy them, read them, believe them; or else buy them, read them, make fun of them. Those Scriptures know how to hold people guilty who read them and don’t believe."
Source: John E. Rotelle, O.S.A., ed., WSA, Newly Discovered Sermons, Part 3, Vol. 11, trans. Edmund Hill, O.P., Sermon 198.20 (Hyde Park: New City Press, 1997), pp. 195-196..
For an excellent compilation of quotes of the Church fathers teaching on the primacy, sufficiency and ultimate authority of Scripture, get a copy of Holy Scripture:The Ground and Pillar of Our Faith Vol III- The Writings of the Church Fathers Affirming the Reformation Principle of Sola Scriptura.