Tertullian, On Baptism 12

When the rule is laid down that no one attains salvation without Baptism, based on the Lord's own pronouncement—"Unless someone is born of water, he will not have life" (John 3:5)—some people raise scrupulous, or rather reckless, objections: how can the Apostles qualify for salvation under that rule, since we do not find them baptized in the Lord, except for Paul? Indeed, since Paul alone among them put on the Baptism of Christ, either the verdict on the danger facing the rest, who lack Christ's water, must be prejudged so the rule stands, or the rule itself must be scrapped if salvation is also established for the unbaptized. I have heard such arguments, with the Lord as my witness, so no one may think me so lost as to stir them up voluntarily out of a lust for writing that only sows scruples in others. And now I will answer, as best I can, those who deny the Apostles were baptized.

If the Apostles had undergone the human baptism of John and desired the Lord's baptism, since the Lord Himself had defined there is only one Baptism, saying to Peter when he refused to be washed: "He who has been washed once has no need to be washed again"—a statement He would never have made to someone who had never been baptized at all—then that is the evident proof against those who strip the Apostles even of John's Baptism, just to destroy the sacrament of water. Can it be believed that the way of the Lord was then being prepared in those persons, that is, the Baptism of John, who were destined to open the way of the Lord throughout the whole world? The Lord Himself, who owed no debt of repentance, was baptized; was it not necessary for sinners? So what? Were the others not baptized? But they were not Christ's companions; they were rivals of the faith, teachers of the law, and Pharisees. From this it is also suggested that, when those who opposed the Lord refused to be baptized, those who followed the Lord were baptized, and did not share the taste of their rivals—especially when the Lord to whom they clung extolled John in testimony, saying: "No one is greater among those born of women than John the Baptist."

Others forcibly argue that the Apostles then fulfilled the role of Baptism when they were sprinkled and covered by waves in the boat, and that Peter himself was sufficiently immersed when he walked on the sea. In my opinion, however, it is one thing to be sprinkled or overwhelmed by the violence of the sea, and another to be baptized by the discipline of religion. Moreover, that boat represented the figure of the Church, which is tossed in the sea—that is, the world—by waves—that is, persecutions and temptations—while the Lord sleeps, as it were, in patience, until He is roused by the prayers of the Saints in the last days, restrains the world, and grants tranquility to His own. Now, whether the Apostles were baptized in some way or remained unbaptized, and whether the Lord's saying about one washing, spoken through Peter's person, applies only to us, it is still far too reckless to speculate on the Apostles' salvation. For them, the privilege of the first calling, and from then on of intimate familiarity, could confer the compendium of Baptism. They followed the One who promised salvation to every believer: "Your faith has saved you," He said, and "Your sins are forgiven"—certainly to the believer, not to the baptized. If that was lacking to the Apostles, I do not know what faith they possessed; with a single word of the Lord, the tax collector rose and abandoned his post; he deserted his father, his boat, and the trade by which he sustained his life; he disregarded his father's funeral: he fulfilled that supreme commandment of the Lord—"Whoever prefers father or mother to me is not worthy of me"—before he had even heard it.