Continuing our discussion on the Church Fathers and baptismal regeneration…
“This discussion of the sacred significance of that water of ours in which the sins of our original blindness are washed away and we are set at liberty unto life eternal, will not be without purpose if it provides equipment for those who are at present under instruction, as well as those others who, content to have believed in simplicity, have not examined the reasons for what has been conferred upon them, and because of inexperience are burdened with a faith which is open to temptation. And in fact a certain female viper from the Cainite sect, who recently spent some time here, carried off a good number with her exceptionally pestilential doctrine, making a particular point of demolishing baptism. Evidently in this according to nature: for vipers and asps as a rule, and even basilisks, frequent dry and waterless places. But we, being little fishes, as Jesus Christ is our great Fish, begin our life in the water, and only while we abide in the water are we safe and sound. Thus it was that that portent of a woman, who had no right to teach even correctly,1 knew very well how to kill the little fishes by taking them out of the water.” On Baptism 1
“And so they say, “Baptism is not necessary for them to whom faith is sufficient; for withal, Abraham pleased God by a sacrament of no water, but of faith.” But in all cases it is the later things which have a conclusive force, and the subsequent which prevail over the antecedent. 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 with 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.” On Baptism 13
I have seen the highlighted portion used to point to an idea that someone the Church added baptismal regeneration as a developed doctrine – however, Tertullian is clearly saying that in the days of Abraham, baptism was not required, but now after the death, burial and resurrection of Christ baptism is a must.