Matthew 4: Then Jesus was led by the Spirit into the wilderness to be tempted there by the devil. 2 For forty days and forty nights he fasted and became very hungry.3 During that time the devil came and said to him, “If you are the Son of God, tell these stones to become loaves of bread.”

two of the three things the enemy tempted Jesus with.. he started out by saying "if you are the son of God".. Jesus never even responded to that... He had no doubt of who He was in God... 

now think about that... Jesus didn't hear God's physical voice.. He had an earthly father and mother and brothers and sisters... yet He knew in His heart and spirit that He was the messiah.. that this was His purpose.. His calling.. His position... 

how many times have we heard God tell us who we are in Him, yet we doubt and are unsure... we don't have that faith and belief that Jesus had to just know who we are... how tragic that we cannot just hear and fully believe...