Doesn't the Bible require faith and repentance for baptism? How can babies be baptized?
Space does not permit the extensive answer this question deserves, so I recommend that readers obtain a copy of Karl Keating's book Catholicism and Fundamentalism, in which Mr. Keating devotes an entire chapter to this question. Still, I'll attempt an adequate defense of the Church's teaching on the subject of infant baptism.
Origen (185-255) declares infant baptism an apostolic institution (Epis. ad Rom., 5:9), and necessary to cleanse the infant of original sin (In Lev. 8:3). St Cyprian and the bishops of the Third Council of Carthage (253) taught that children should be baptized as soon as possible after birth. Their baptism was not to be deferred until the eighth day, as some had maintained.
"He came to save all who through Him are born again unto God; infants, and children, boys and youths, and elders." (Adv. Her., 2:22).