Only had him a few weeks :-(

I'm going through the exact same thing with my newest snake too George. I got her on a month ago and she hasn't taken a meal yet. It's frustrating but the hunger will win in the end :). The other members have given great advice. As hard as it is, don't handle or disturb him until he's eaten for you a couple of times. How are you thawing your rats? Are your prey items completely thawed and served warm? And finally what are your temps like and is your heat source controlled with a thermostat? Make sure your husbandry is dialed in and he'll eat eventually. If he's 3 years old he might just be looking for a girlfriend and not have an interest in food right now. And just to repeat what Kira said, some snakes will fast during the colder months. I've had snakes not eat from November-March and they were just fine. Keep offering him food every 7-10 days and he'll come around. Best wishes.

i have a new addition that hasn't eaten as well, though she finally showed interest last feeding but did not take. like another user mentioned: try leaving the prey item in the enclosure overnight, and maybe cover the enclosure with a blanket to give the snake some privacy and they might take it.
read through ziggy's post and make sure your prey item temps and husbandry is spot on. like he said: hunger will win in the end. ;)

O/P, it sounds to me as if you are trying to feed too frequently and are handling the snake too often.

If the age of the animal is 3 years old, there is NO issue with it refusing food for only a few weeks. Our royal has gone almost a full year with only one meal. There was little to no weight loss over that time period. Snakes are masters of efficiency when it comes to regulating their metabolisms and feeding. They are able to survive/thrive very long periods without eating.

At this point you need to let the snake settle. I didn't catch the species??

Sometimes it is a good idea to set the snake up in a similar fashion to how it was living prior to you taking it in. That all depends on the skill/knowledge of the previous owner.

As far as handling, the snake will tolerate you, but it has to become used to its new surroundings first. Otherwise your handling is just adding stress. 3 weeks in a snakes life is a blink of an eye to them. These are "long haul" animals and they need time and patience.

Just to put you at ease, my boa constrictor has not eaten since early November and will not eat until early April. He will be bigger and healthier come the warmer months guaranteed.

Wait and I'll bet the snake will eat eventually. Spring is coming and most of my snakes will become more active and naturally want more food.