Sinless Jesus

Jesus Lived a Sinless Life
"Jesus the Son of God, . . . has been tempted in every way, just as we are - yet was without sin."-Hebrews 4:14, 15.
Jesus lived a real, flesh-and-blood life of moral perfection. By going through all the trials of human existence, Christ made a life free from sin far more attractive than any sermon ever could.
Satan, Christ's great adversary, plotted throughout Jesus' earthly life to seduce Him into sin. When Christ fasted in the wilderness, the devil assaulted against Him (Matthew 4:1-11). And during the night in the Garden of Gethsemane, the pressure of temptation reached such intensity that Jesus sweat drops of blood (Luke 22:44).
No one else has had to face such a demonic assault. But Christ stood firm against everything the devil could throw at Him-"yet without sin." Because Jesus experienced the full range of human problems and temptations, He understands our struggles and needs. He is able 'to sympathize with our weaknesses' (Hebrews 4:15).
Why was it necessary for Jesus to live a sinless life?
"God made him [Christ] who had no sin to be sin for us, so that in him we might become the righteousness of God."-2 Corinthians 5:21.
We might paraphrase this passage, "God made Jesus, who was sinless, to be sin for us; and in place of our sinful life Jesus gives us His sinless life, that we might be made sinless in Him."
If Christ did this for us, why is it not possible to lead a sinless life? Why are we so prone to sin? If we are in Him, then we should be the 'righteousness of God' so how true is it that we are "in Him" or does God allow us to reside in Him because He can relate to our weakness?
