Welcome to the forum, congratulations on your Quaker.
One day, I bet he is afraid, everything's is new, he doesn't know you or what's going on.
What is the size of your cage? Smaller cages, make them feel more stress. Also have the back of the cage against a wall, and always approach from the front and talk to him.
If this was me, I would put a small treat only dish in the cage. I would use safflower seeds as my treat. Then I would move a chair and sit at one end of the cage, turned sideways so I'm not just staring at the poor guy. I'd say hello " name" show one seed, and out the seed inn the dish. Then I'd sit there reading out loud my text messages, or a book. Until he seems relaxed to have you there, and hopefully takes the treat. Then I'd go for stuff for a few minutes, and come back and repeat. Also I would come to the cage several times a day say hi, put a treat in the dish and walk away.
I would set up the top of the cage and the outside side of the cage with a few perchs and also out a treat dish at the top of the cage. I wouldn't let him out for a couple of days, until he is calm with you sitting beside the cage everytime. Then I would let him out , after still doing the hello and seed treat and sitting there for a little while. When he is calm, just open the door, and then just sit there still just talking to him. If he climbs to the top and hangs out. Then I would do some stuff near by and come to say hi several times, putting a treat in the dish on top of the cage. Working up to feeding the treat by hand.
I'm going to link another thread where I and others have a bunch of advice.
http://www.parrotforums.com/quakers/83780-help-needed-new-quaker.html