Around 400 AD, a man named Augustine came up with the idea of “original sin.” This basically said that everyone inherits the sin of Adam at birth and is therefore separated from God from the beginning of their life. Of course, this caused parents to become concerned over the fate of their children, should they die before “getting right with God.” Since only one of the four steps required to get right with God could be done by (or to) an infant, they decided to baptize them to “take care of the original sin.” Since it is risky to immerse an infant, these people decided to sprinkle them with water instead. Thus, both baptizing infants and baptizing by sprinkling came from human ideas. They did not come from the Bible.
If we look in the Bible we see that children are never seen to “accept Christ” (and therefore get right with God). It is also interesting that God never tells us what to do to keep a child safe. Did He just forget this important point, letting many children go to Hell and suffer eternally? No. A child is safe in the arms of God until they can understand how to be saved by accepting Jesus as their savior. (See 2 Samuel chapter 12, verses 22 and 23 along with Matthew chapter 18, verse 10.) Thus, only adults and older children (who can understand separation from God because of sin and so forth) are at the age when acceptance of Christ is possible."
What is Baptism?