Same reason He told all Jewish males to cut off their foreskin? Oh wait, that was so they could avoid getting sand up in there. :bigyikes: Very uncomfortable.
No, seriously though, it wasn’t an exact replacement for circumcision, but it’s done for very similar reasons.
Be honest. Haven’t you had similar thoughts about that? When baby boys are eight days old, you cut a little bit of skin off the penis. Why? Because God commands it. Didn’t that sound kind of funny to you when you first heard it? What’s God going to do with the foreskin, anyway?
Haven’t you ever wondered why YHWH would command that Jews do something absolutely useless like that?
Well, whether you have or haven’t, the question has been asked before and you know the answer to it. Now you’ve asked the same question about baptism, and the answer is basically the same- the only major change is that you replace YHWH with Jesus.