c. 198–203 · Tertullian, On Baptism (De baptismo) 13
Grant that, in days gone by, there was salvation by means of bare faith, before the passion and resurrection of the Lord. But now that faith has been enlarged, and is become a faith which believes in His nativity, passion, and resurrection, there has been an amplification added to the sacrament, viz., the sealing act of baptism; the clothing, in some sense, of the faith which before was bare, and which cannot exist now without its proper law. For the law of baptizing has been imposed, and the formula prescribed: “Go,” He saith, “teach the nations, baptizing them into the name of the Father, and of the Son, and of the Holy Spirit.”