How infant baptism came to be? In my understanding of church history, it started when Constantine made Christianity the official religion of the Roman empire. A former pagan empire, now to be made Christian. Christianity now a state church, was faced with a huge influx of pagans to be made Christian by baptism.
The state church saw the pragmatic, and much faster, answer to the problem, was to just sprinkle water on them. Once the former, and Biblical, mode of baptism was compromised, it was just a matter of time before they rationalized again, and began to sprinkle infants as their baptism.
Not true. Infant baptism has been around since the earliest days of the church. I don’t have time to look up chapter and verse right now, but the gist of it was that a “head of household” became Christian, and the entire household (including infants) was baptized and came into the church with him.