I struggled with that same question myself booboy, and here's the conclusion I came to:
I realize that in the Christian (my own) religion, our bodies are seen as the vessels of God. Essentially, we're supposed to treat our bodies well as far as nutrition goes, but also indicating that we're not supposed to hurt ourselves or put anything into our bodies that said God wouldn't be too happy about. However, due to our gynecomastia, our self image is hurt. In some cases, drastically. For me personally, every time I looked in the mirror with my shirt off, I was disgusted at what I saw. I didn't necessarily hate myself, but I did hate the way I looked. It was killing my self-confidence as well, overall making me mildly depressed 24/7. Then I asked myself, "Is this the way God would want us to live, hating the way we looked?" Obviously not. Even though we are raised, as religious people, that God made us in his own image, I think there is something else to be had about going through with the surgery. For me, it was getting closer to my parents, especially to my dad. Ever since I first opened up to him my concerns about my problem about 3 months ago, I feel like I can talk to him about absolutely everything now. It's helped me develop a stronger trust and respect for him, something God (as our 'Father') definitely wants for every son and father. Not only that, but after the surgery, our confidence levels should skyrocket. I know that my mom and brother have even told me that I appear to be a lot happier and carry myself in a different manner, and I haven't even HAD the surgery yet.
It's a delicate question that I once struggled with myself, but I don't see anything wrong with going through a minor surgery to help better our personalities and confidence. And, it'll make us happier, altogether.