Augustine-Baptism of Faith

Letter 98, to Boniface.
Boniface asks "Why do we ask the parents questions about the child's belief when the child is obviously not capable of believing." The baptismal liturgy went something like this.

Minister: Does this child believe in God?

Parent: Yes, he believes.

Part of Augustine's answer is this, "...the answer is made that he turns himself to God because of the sacrament of conversion..."

And also, "Therefore an infant, although he is not yet a believer in the sense of having that faith which includes the consenting will of those who exercise it, nevertheless becomes a believer through the sacrament of faith."

So, in Augustine's thinking, baptism was the sacrament of conversion and made the infant a believer.