Was Jesus really a human being or only pretending to be one?
Of course He was a human being. I don't know how anyone who has read the bible could deny this. I do not see how any Christian could go down the road of saying He could pretend. He did no sin, in Him was no sin, He knew no sin, He was undefiled, He could not sin because He was still God.
What do these verses teach?
I am amazed at His humility and His great love for me. Whenever I read them I love Him even more.
What difference does it really make whether or not Jesus was human?
Jesus had to become a Man in order to be our Substitute and bear our punishment. There was none other good enough. Also He showed us how to model our lives, and He shows us He understands, and I think that when we reach heaven we will not see God the Father but we will see God the Son because He put upon Himself humanity.