Polycarp, bishop of Smyrna (69-155/156):
"These things, brethren, I write to you concerning righteousness, not because I take anything upon myself, but because ye have invited me to do so. For neither I, nor any other such one, can come up to the wisdom of the blessed and glorified Paul. He, when among you, accurately and steadfastly taught the word of truth in the presence of those who were then alive. And when absent from you, he wrote you a letter, which, if you carefully study, you will find to be the means of building you up in that faith which has been given you, and which, being followed by hope, and preceded by love towards God, and Christ, and our neighbor, “is the mother of us all.” For if any one be inwardly possessed of these graces, he hath fulfilled the command of righteousness, since he that hath love is far from all sin."
Source: ANF: Vol. I, The Apostolic Fathers, the Epistle of Polycarp to the Philippians, Chapter 3.
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.