Jesus own words demostrate his authority.  He came to do the will of the Father and demostrated obedience.  His claims point to Him being one with God. 

My Muslim friends, although I have few, find this concept very difficult.  How can one come in human form as a baby and experience humanity"  To them, he was a prophet and nothing more.  

My friends who have not experienced Christ see him as a "good teacher, but not the Son of God, one of the most influential teachers in history."  If they study the scriptures they'll find that Jesus could not be just a teacher.  His claims either made him a lunatic, or he was the Son of God.