From the ancient church, Theodoret of Cyr:
If the only meaning of baptism were remission of sins, why would we baptize newborn children who have not yet tasted of sin? But the mystery of baptism is not limited to this. It is a promise of greater and more perfect gifts. In it are the promises of future delights. It is the type of the future resurrection, a communion with the master's Passion, a participation in his resurrection, a mantle of salvation, a tunic of gladness, a garmet of light, or rather it is light itself.
From The Ancient Christian Commentary on Scripture, New Testament IVa, John 1-10, p 114.