What exactly does baptism do?
Baptism is best known as a Christian sacrament of initiation into the faith. It's been around ever since the beginning of Christianity and the practice can be traced back to John the Baptist of the New Testament baptizing Jesus. A lot of people ask what happened to the souls of the early Christian martyrs who hadn't yet been baptized before they were killed. The Church says that they were given a Baptism of Blood. Otherwise people who wanted to be Christian but were killed before they were able to succeed in that wish were considered being given a Baptism of Desire.
All of this focus on baptism comes from Jesus saying that unless one is born again of water and the Spirit, he cannot enter the Kingdom of God.
The word 'baptism' is from the Greek, which means washing, as in ritual washing. Original baptisms were done by total immersion. The idea here was to wash away all sins by dying to sin and reemerging as a new person. Nowadays, most baptisms are by Aspersion, which is sprinkling water on the subject's head. This is done in deference to the practice of baptizing infants. This was not the case in the early Church. Only adults who had undergone a period of learning the faith from a sponsor and much prayer and sacrifice could be baptized. In other words, receiving baptism was the final act of total acceptance of the faith.
Since early Christian baptism had the subject naked, deaconesses helped women go through this ritual. This is proof that the early Christian church had female deacons, meaning that women played a role in the practice of Christianity. This all changed in the Middle Ages when women were relegated back to subservience as far as the totally male clergy was concerned. Removing all clothing was considered a way to throw off the old ways of sin. Once the subject was baptized by immersion, he or she was given a white garment, symbolizing purity of the soul, proof that baptism was considered a way to forgive sin and remove the punishment due to it.
So, baptism is considered a form of rebirth that is made possible by water and the Spirit, as in the Holy Spirit. Many Christians, especially Catholics, think that baptism is a magic trick; pour a little water on the head and bingo, you're saved. That's not how it works. Sacraments are outward signs of spiritual events, and the spiritual event of baptism is conversion from a life of sin to a life of faith. Unfortunately, this concept has been distorted by allowing infant baptism. This occurred in the Middle Ages after Christianity took over the Western world, and since most people were Christian anyway, they petitioned the Church to baptize their children. The Church relented and this is how the practice became a weak token of its former purpose. Now it's nothing more than a thing to do to a newborn. Baptism includes finding a sponsor for your child. The sponsor is supposed to see that the child is brought up in the faith, but again, this practice is a token.
Baptism is and should be an initiation into the faith. It's a way to signify for the congregation that the baptism candidate is going to be a practicing member of the church. I emphasize practicing because that isn't what usually happens. Many Christians are of the fair weather variety. Their fervor for the faith has been lost and smothered in the secular ways of the world.
Thanks for reading.