My ball python suddenly hates being touched

[Bogertophis]

Thanks for the help! I think you are right when I first got him he was under weight and didnt have alot of energy would mostly stay in his hid which is understandable the lady I rescued him from was not feeding him the correct size meal shed feed one small mouse every 14 days. I haven't brought him out since he started being defensive because I didnt want to stress him out for now I'm just putting my hand in his tank for him to smell and light touches on his back.

Sounds good...he has to re-learn to trust people around him, or maybe even for the first time, IMO.
And since he's four years old, it make take him longer to adjust...just be patient.

Then again, I re-read the first post & maybe it's really those "explosions"? That would make ME nervous too. (sorry, I had to!)

...when I first got him he didnt mind being held and being out of his tank exploding ...