IntolerantElle has a question for those who see baptism as a means of grace. Why do parents not baptize their children as soon as possible after birth? Now I believe she has in mind the Lutheran view, but Presbyterians have some answer to this question that I don't think is available to Lutherans. The extent to which they see baptism as a means of grace isn't any more than Baptists see baby dedications as a means of grace, which is pretty much equivalent to how all Christians see preaching, godly correction, Bible study, or the gift of encouragement as a means of grace. What's more difficult is if you mean something stronger in seeing it as a means of grace, which I think Lutherans do. But the most intriguing element of her post is the closing line, because it raises the issue that most fundamentally convinced me of the wrongness of paedobaptism, and it's something so radical that I refused to believe that paedobaptists really taught this until some of them insisted on it to me as an argument for their view. IntolerantElle says, "I know I couldn't stand to look my newborn in the eyes and know I was the one responsible for keeping him from being part of God's family."
That's what I think is the biggest anomaly in the paedobaptist view. The idea is that baptism brings you into God's family, as if outward washings are the effective agent of who is in Christ and who isn't in Christ. I think you'd be hard-pressed to convince Paul that what brings someone into Christ is outward baptism rather than an inner work of God. Presbyterians are more likely to say that a baptized infant is now in the covenant, but it amounts to the same thing. Those in the covenant are those in God's family. What's odd to me is that they end up denying that someone in the covenant is saved, which amounts to saying that those in God's family aren't all saved. There are genuine reprobates in the new covenant and thus in the family of God, which means there are genuine reprobates who are in Christ. They won't remain in Christ, and thus they're not elect, but that doesn't stop this view from undermining the fundamental biblical divide between those in Christ and those not in Christ.
I say this as someone who happily attends a congregation that will honor parents' convictions on this issue, which I think is the correct view for a congregation to take, and I say it as someone who sees what paedobaptists doing with their children as the same as what credobaptists do when they decicate (with confirmation and credobaptism as serving the an equivalent purpose at an older age). My willingness to say all that doesn't stop me from thinking the paedobaptist view is false.