Justin Taylor discusses Wayne Grudem's second thoughts about churches allowing individual pastors and families to make the decision regarding believers vs. infant baptism for themselves, a la the Evangelical Free Church of America. Grudem recognizes that the differing administrations of baptism do imply differing theological convictions about baptism and what it means, and appears to be moving toward a more traditional Baptist position.
Although my convictions are also strongly in favor of believer's baptism, in seminary I did have to grapple with the issue of solid Christian brothers whom I knew to be serving the Lord with all their hearts who had been baptized as infants and were satisfied that their baptism was legitimate. Since I recognized from Colossians 2:11-12 the important parallel between circumcision and baptism--essentially, baptism functions like circumcision in the Old Testament: it is the entrance and sign of being among the covenant people--I therefore couldn't regard it as a simple doctrinal difference. If infant baptism has no legitimacy whatever, then an infant-baptized Christian is an unbaptized Christian, which is sort of analogous to an uncircumcised Jew!
Baptism was essentially the New Testament altar call.The position I eventually came to is this: faith is what validates baptism. This may seem a little obvious, but there are large implications once it is fleshed out a little. Faith validates baptism regardless of whether that faith comes prior to or subsequent to baptism. I'm still convinced that the biblical model is that one enters into baptism as a profession of the faith that one has already entered into--i.e., baptism was essentially the New Testament altar call. So it's really appropriate only to believers. But I also believe that if a person were baptized before coming into faith (e.g., as an infant), and that person subsequently did come into faith in Christ, that person's faith in Christ would validate the baptism that he or she had already undergone. Such a person would, in fact, be a baptized believer. I would have no objection if a person who had been baptized as an infant and later came to faith chose to be rebaptised--once again, as a profession of faith and as a sign of having come into the covenant community--but if that person chose to accept his or her infant baptism as now legitimate, having been validated by their faith, I would have no objection to that either.
So as a pastor, I would only baptize those who had come to faith. As a father, I have only allowed my children to be baptized when I felt that they were able to make a credible profession of faith. This, as I said before, is because it is faith that validates baptism; there is no reason to baptize someone who has not come into faith in Christ. The great danger of infant baptism is that it gives a false sense of security; people believe that their status with God is acceptable because they have been baptized as infants. (It also has the tendency to "lock" a person into a particular denomination before they have the ability to choose.) Nonetheless, as a believer, I will look on a person who trusts in Christ for salvation and has been baptized as an infant as a fellow baptized believer, because I believe that that person's faith in Christ has validated the baptism they had as a child.