According to what is delivered there are only a few unsure cases where there might have been infant baptisms but it was surely not usual.

The church's writings delivered from the first two centuries AD are the New Testament, "The Apostolic Fathers" and the Apologists. The fact that none of these explicitly commands infant baptism, nor mentions that babies were baptized, does not prove it was common not to baptize infants at that time.

It is not necessaru to command what is already being done as a matter of course ot to mention what everyone already knows.

By the end of the second century, among some Christians in some places, it was common to delay baptism. The reason was that these people had the notion that baptism is for past sins, and that they ought to delay baptism until they were less likely to be tempted to sin.

That is why Irenaeus of Lyons, late in the second century, wrote that infants should be baptized at the age of one week. Hippolytus of Rome wrote, around 200 AD, that the infants of converts should be baptized when the parents were baptized.

They were not teaching something that had not been done in the first two centuries, but reproving some people who were not doing what had been done since the days of the apostles.

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