As Dave Hamlin pointed out a while back, when you attempt to study baptism you soon end up trying to understand covenants. Based on my reading of Welty, here is the basic Reformed Baptist argument: "The New Covenant is unbreakable and is made only with the elect. Baptism is the sign of the New Covenant. Therefore only the elect should be baptized." Also, there seems to be a presupposition that a "credible profession of faith" indicates someone is elect. Since infants cannot profess, they are not to be assumed elect and thus mustn't receive the sign of the New Covenant.

Before I can accept or reject any argurments, I need to understand the position. So I plan to read the best I can find from the Reformed Baptist perspective to ensure I correctly represent this position.