Part of me thinks if you guys really truly want to do this, healing may be quicker now at 4 months. The child isn't as mobile yet and you can just let him lay on blankets so diapers/clothing aren't adding discomfort. Later though, your child could communicate his need for pain pills, food etc while recovering. I think that's a pretty big deal.
I'm pretty sure you guys have covered this, but if I am not mistaken, there are several religions out there whose views of circumcision have changed or been altered somewhat. If you guys haven't done so already and you really don't want to do this, I'd try talking to someone to see if circumcision is an actual requirement of your faith. DH and I were both brought up in families who circumcised and it was the "normal" thing for everyone we knew. Many touted religious belief but when all was said and done as we studied after (sadly it was after) our first son was circumcised, we realized there really wasn't anything saying we "had" to circumcise.
I have one son circumcised and one not. The one who is not is a result of what happened to the one who was. I really never would have questioned it otherwise. It has been horrible and it has literally only been in the last few months that I can see my oldest son and not want to cry. I'm still ridden with guilt. He is now 5. I know soooooo many little boys nothing happened to. I can't begin to put into words what it feels like to be the mother of a son who has complications due to circumcision though. There actually are no words to express what it is like.
If you really do not want to do this, I'd start checking to be sure that you actually have to in order to stay within the guidelines of your religion.
I'm sorry you are in this tough spot with your wee guy