golden retriever

I just adopted a rescued puppy from a local animal rescue, its a golden retriever named Sonny. He was abused as a puppy and so is very afraid of my wife and I, but we have only had him for a day so we hope he will get better. One of our main concerns is getting him to go outside, he refuses to go outside, and unfortunately we have not been able to get too close to pick him up or anything. Does anyone have any advice?