Need advice for neutering

Please don’t laugh at me. I need genuine advice. My male cat will get fixed tomorrow morning. I have already cancelled this procedure 3 times before. He hasn’t start spraying yet. I feel SO guilty I feel like I’m doing something wrong. He is really horny though and I feel like it’s torture for him. Why does it feel so wrong though? I’m also a Christian and I’m scared that this is a sin. Again I need genuine advice and no judgement. Is this a sin? I feel so bad. And I’m also afraid I’m gonna lose his personality. He’s a crazy cat, and me and my husband are afraid he won’t be the same after. Please please help me. PS He’s an indoor cat so the issue of him getting another cat pregnant is 0%. We live in an apartment and he never gets out