Does he like me or is he playing with me? ADVICE!!?

Okay there is this guy (we shall call him Bob) okay bob shows all the signs of liking me (such as physical contact a.k.a. hugging, and pushing around and spending time together, smiling and joking alot) when asked by some people if he liked me he said yes...but when it comes to him asking me out (yes i like him) he seems to try to change the subject or joke about it. He says he's afraid of commitment, but im not sure if that's what he means or if he really is just playing with my feelings. I have known him for some time and believe he is more or less a good person. I just don't understand why he won't ask me out (i don't want to ask him myself since it seems shaky as whether or not that's the right thing to do at this point) any helpful advice is welcomed, thank you!