Is my married coworker flirting with intentions?

It all started with a class we had together, I sat by him at the same table and he spoke out loud in class as he's the bold, direct, loud type. It embarrassed me, so I laughed nervously and maybe he took this as interest? After that, he started flirting with me, making eye contact, smiling at me and once he even winked at me. I am always cordial and smile back, but for the most part, I have pretty much ignored him. He is happily married, a bit religious too, that's why this is all so very puzzling to me. He speaks of his wife often to others but then he flirts with me once he turns around. He started bringing my copies to my desk off the copier before I ever had the chance to go get them. He would stutter and stammer and get all red-faced and couldn't speak. I would do the same as he is a bit intimidating to me. He is very well-respected and well-liked in the office and has never flirting with any sexual connotations at all. Mainly he just teases me and nudges me all the time. Then he started pacing back and forth in front of my cubicle always looking in and smiling real big. Now he has to make eye contact with me and smile every morning or he will pace back and forth past my desk until I look up and he can smile at me. What is he up to? Am I his ego boost or what? He never asks me any questions, but when I'm off a day, he comes and asks my coworkers where I'm at. One time I moved desks and my friend said he looked panicked when he walked by and I was no longer sitting there. Then he went around and asked everyone why I had moved. But he never asked me a thing. My friends have all noticed his behavior, I'm just afraid other coworkers will soon notice it too. He is a sweet guy, I can't fault him for that, but sometimes he's over the top, like dressing up in my favorite team's colors even though it's not his favorite team. Everything just to impress me. I don't understand it. Once he gets a smile out of me for the day, he is on cloud 9 and strutting around like a peacock. He started going to the gym, has lost weight, is dressing nicer and everywhere I go, there he is.