Each of us knows what it is like to sin. When you tell a lie, hold a grudge, cheat, kill or steal, you are sinning. Other sins are more subtle, such as pride, greed or arrogance. According to Jesus, even the way you think can be a sin. Jesus Christ is the only person who never sinned.
"In the past God spoke to our forefathers through the prophets at many times and in various ways, but in these last days He has spoken to us by His Son, whom He appointed heir of all things, and through whom He made the universe. The Son is the radiance of God’s glory and the exact representation of His being, sustaining all things by His powerful word. After He had provided purification for sins, He sat down at the right hand of the Majesty in heaven. So He became as much superior to the angels as the name He has inherited is superior to theirs.
"For to which of the angels did God ever say, 'You are my son; today I have become your father?' Or again, 'I will be His father, and He will be My son?'
"And again, when God brings His first born into the world, He says, 'Let all God’s angels worship Him.' In speaking of the angels He says, 'He makes his angels winds, His servants flames of fire.'
"But about the Son He says, 'Your throne, O God, will last forever and ever, and righteousness will be the scepter of your kingdom. You have loved righteousness and hated wickedness; therefore God, your God, has set you above your companions by anointing you with the oil of joy.'" (Hebrews 1:1-13)
He was tempted, because He was human. But He overcame sin because He was God. In the Old Testament, priests would make sacrifices for sins. Jesus is the ultimate high priest. "Since we have a great high priest who has gone through the heavens, Jesus the Son of God, let us hold firmly to the faith we profess. For we do not have a high priest who is unable to sympathize with our weakness, but we have one who has been tempted in every way, just as we are -- yet was without sin." (Hebrews 4:14-5:6)
As the sinless Son of God, Jesus Christ is a better revelation of God than words written by prophets, a better messenger than angels, and a better representative than a human High Priest. His enemies could not accuse Him of sin; no one could find anything that He had done wrong. He alone, as the matchless Son of God, lived as a human being -- and as God -- without sin on this earth. He did this so He could be the perfect sacrifice for us, so we could experience something better in our lives -- a relationship with God anchored in His completed work.