Many people have attempted this before and failed, so I don't expect that I will succeed in changing his mind that Infant Baptism is just plain wrong. I do want to make it clear that my purpose is not to claim one wrong and the other right; or to claim one is better than the other. After long thought and prayer, I have determined that the theologies behind the two traditions of baptism are very different.
Baptists and those who believe in Believer's Baptism believe it is just that - baptism once you believe. Some of them will even claim that you aren't really saved unless you've been baptized after confession. I don't agree with that group of people - I strongly believe that salvation does not require baptism to be true. I believe that baptism is simply an expression of faith, like fasting and long hours of meditation.
To those that simply believe baptism shouldn't occur until after belief is established, I don't disagree with you and your theology. I find it a good thing. However, I also find that Infant baptism serves its purpose, as well - and is, in fact, biblical. It simply derives its theology from something much older.
This is in two parts. The first addresses the theology behind infant baptism. The second tackles some conceptions that I think are false when it comes to belief in Christ.
First, when Christ came, he made it clear that he was not coming to abolish the law, but to fulfill it (Matthew 5:17). There were commandments that were given in the Old Testament by God to prepare the people for the coming of Christ. Examples are the command to never forget the passover - for the signs given at the passover were repeated when Christ died...and anyone who religiously practiced the passover meal would have recognized those signs (Exodus 12:14). There are others, but hashing this point isn't relevant to this argument.
Another command that was given was that when a gentile chose to become a follower of Jehovah, he had to be circumcised (Genesis 17:10-11) - and so did his whole household (Genesis 17:12-14). In essence, when one chose to become a part of the covenant, his entire family was commanded to become a part of the covenant - regardless of their own feelings on the issue. Examples of this being carried out in scripture include Dinah's lover and his kingdom (Genesis 34) and the risk of Moses' son's life due to his lack of circumcision (Exodus 4:24-27).
Because the Catholic Tradition of baptism is one of a convenantal nature, its theology derives from the Old Testament's method of entering the covenant.
Where Believer's Baptism is an expression of faith of the person being baptized, Infant baptism is an expression of faith of the parents of the child being baptized. To them, this is their declaration of their covenantal bond with Christ a promise to do as God commanded in Deuteronomy - not once, but twice.
5 Love the LORD your God with all your heart and with all your soul and with all your strength. 6 These commandments that I give you today are to be upon your hearts. 7 Impress them on your children. Talk about them when you sit at home and when you walk along the road, when you lie down and when you get up. 8 Tie them as symbols on your hands and bind them on your foreheads. 9 Write them on the doorframes of your houses and on your gates.
18Fix these words of mine in your hearts and minds; tie them as symbols on your hands and bind them on your foreheads. 19 Teach them to your children, talking about them when you sit at home and when you walk along the road, when you lie down and when you get up. 20 Write them on the doorframes of your houses and on your gates, 21 so that your days and the days of your children may be many in the land that the LORD swore to give your forefathers, as many as the days that the heavens are above the earth.
In the Catholic Tradition, parents take full responsibility for their child's faith until they are adults and can claim responsibility for their own faith - just as the jews did and still do when their children come of age. In the Catholic Tradition, it is Confirmation. For the Jews, it is a Bar or Bat Mitzvah - a ceremony where the now young adults take everything they have learned from their parents and accept it as their own faith.
And this brings me to the second part - the matter of belief. Many who believe in the Believer's Baptism believe that only when a person reaches an appropriate age of responsibility can he make a concious claim of faith. The Catholic Tradition doesn't place that stipulation on belief. An 18 month old singing songs in her crib as the sun pours through, conciously aware of the one who created the sun, is capable of true belief. The 4 year old who cries when Jesus dies in his children's bible and shouts with joy that "Jesus is alive!" when he comes back to life is just as capable of true belief. The 6 year old who gives her favorite bible away to a girl whose parents are atheists because she was asking questions about God and Jesus is just as capable of true belief. Even Jesus claimed that more people should have faith like children. If we all had such blind faith like children, wouldn't that mean that none of us should be capable of a concious, reasonable decision of faith? (Matthew 10:15)
For those raised in Christian homes that are taught daily the Christian faith, a child can come to an adult understanding of Christ without ever having that "pivotal moment" of confession and faith. For them, every day is a living confession of faith and there is no remembrance of a life without Christ because he has always been a part of their lives.
And to these children and their parents, Infant baptism is a valid and even right and true expression of faith.
I don't intend for the one who challenged me to change his views on baptism in so much that Believer's Baptism is what he chooses to follow. I do, however, wish to bring about an understanding and graceful acceptance that those who practice infant baptism do so believing it is right and true and that it is just as valid as believer's baptism. And that those baptized as infants do not need to be baptized a second time.