They had also lived in Carthage, Africa.

One finally settled in Jerusalem, and the other travelled among all the churches in the principal places of Europe and Asia.

But they had never heard of the man, not even a heretic, who had denied infant baptism.
Here is another interesting proof.

Irenaeus, Philastrius, Augustine, Epiphanius, Theodoret, wrote catalogues of all the sects of Christians which they had ever heard of; but, while they make mention of some who denied baptism altogether, and with it, according to Augustine, a great part of scripture, they mention no denial of infant baptism by any sect whatever.
_Mr.M._ I suppose, then, that the only way of disposing of this argument is by rejecting all testimony except that of the New Testament.
Some say they can prove anything from the fathers; so they insist that the Bible alone must be our guide.
_Dr.D._ They are right in making that the only and sufficient rule of faith and practice.

But how do these good people and the rest of us know that the books of the Old Testament, as we have them, were the very books to which Christ and the apostles referred as the word of God?
If infidels refuse to receive the Bible, saying, 'There is no proof that these are the identical books known to Christ, and quoted by him and the apostles,' What shall we say?
The Bible itself gives us no specific direction how to prove its genuineness.