Tertullian

“ 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.” [3] The comparison with this law of that definition, “Unless a man have been reborn of water and Spirit, he shall not enter into the kingdom of the heavens,” [4] has tied faith to the necessity of baptism. ”