The Living Sacrifice- Part 1:

II Corinthians 5:21
For He made Him who knew no sin to be sin for us, that we might become the righteousness of God in Him.

He became the very nature of our sinful flesh upon that cross. Suffering a slow death to fulfill the will of a loving Father who longed to be at peace with us and reconciled with His very creation. 

"For God so loved the world that He gave His only begotten Son, that whoever believes in Him should not perish but have everlasting life. For God did not send His Son into the world to condemn the world, but that the world through Him might be saved. “He who believes in Him is not condemned; but he who does not believe is condemned already, because he has not believed in the name of the only begotten Son of God." 
John 3:16-18

God has planned the best for all of us; The lost would be found. Jesus became that sinner who never sinned. He had become weak (fragile) in His flesh because He was bearing the burden of our sin. His strength was not of His own- and that very strength (God) left (forsaken) Him, so that He could feel affected and conscious of that sin. 

He was crushed & broken- 
Isaiah 53:4-5, 7, 10:
Surely [He HAS borne OUR griefs And carried OUR sorrows]; Yet we esteemed Him stricken, Smitten by God, and afflicted. But He WAS [wounded] for OUR transgressions, He WAS [bruised] for OUR iniquities; [The chastisement] for OUR peace was upon Him, And [by His stripes] WE ARE healed. He WAS [oppressed] and He WAS [afflicted], Yet He opened not His mouth; He was led as a lamb to [the slaughter], And as a sheep before its shearers is silent, So He opened not His mouth. Yet it pleased the Lord to [bruise Him]; He has put Him to grief. 
[When You make His soul an offering for sin], *He shall see His seed, *He shall prolong His days, And *the pleasure of the Lord shall prosper in His hand.

He who knew absolutely NO sin, was accused of sin (sin that never even existed in Him) and began to carry the burden and weight that was not of His own. Jesus took the punishment for us. 
Imagine Atlas carrying the world upon his shoulders. Now view Jesus doing this...
Never sinning- ALL the temptation weighing (Pressuring Him, never giving in) on Him & The sins of the world placed on Him. Heavy load, is it not?
He can sympathize with us- but we can not emphasize with Him. For He drank of our judgement & suffered for us.

Can you imagine being perfect (never sinning) and then suddenly enduring a penalty as if you had lived imperfectly?

Another way of seeing this is looking at a "Super Hero" & watching him fight crime with no powers. He would inevitably become vulnerable.

When we sin or willfully sin- Does not that guilt weigh heavy or destroy your conscience?
When we give into sin, we feel guilty! Immediately we ask for forgiveness! Jesus did not need to seek forgiveness from the Father. 

To ponder Jesus' death and consider dying knowing you had no guilty conscience of your own (He was always obedient), but to have one's (the elected saved souls to come) iniquity placed upon you. To feel guilty without guilt; to know sin, without sinning; to feel wrath upon you as if you were the wicked one...

Proverbs 24:10 NKJV
If you faint in the day of adversity, Your strength is small.

Jesus may have appeared weak/faint, hanging on that tree to those who put Him there, but The Father put Him there to save the very one's who crucified Him. It was the Father's power that delivered strength to Jesus that led Him there to it. If you have the strength of God- you are no longer weak! For He strengthens you where it lacks; in your flesh.

Questions:
Can you imagine how much our sin must weigh? 
Can you imagine how heavy the entire sin of humankind that existed then (past time) and that would exist (present and future), would weigh?

Matthew 11:28-30
Come to Me, all you who labor and are heavy laden, and I will give you rest. Take My yoke upon you and learn from Me, for I am gentle and lowly in heart, and you will find rest for your souls. For My yoke is easy and My burden is light.”

"My burden" is light 
vs. 
"Our burden" was heavy
We can take upon His burden in exchange for eternal life.

He drank from the cup of suffering. 
It's no wonder our sin has been thrown into the sea- that it may swallow it and be no more.

Isaiah 43:25- “I, even I, am He who blots out your transgressions for My own sake; And I will not remember your sins.
Micah 7:19- He will again have compassion on us, And will subdue our iniquities. You will cast all our sins Into the depths of the sea.
Hebrews 8:12- For I will be merciful to their unrighteousness, and their sins and their lawless deeds I will remember no more.”

Could you image the pressure of temptation, But imagine it in a way where you were incapable of giving into it?

Matthew 4:1-11 NKJV
Then Jesus was led up by the Spirit into the wilderness to be tempted by the devil. And when He had fasted forty days and forty nights, afterward He was hungry. Now when the tempter came to Him, he said, “If You are the Son of God, command that these stones become bread.” But He answered and said, “It is written, ‘Man shall not live by bread alone, but by every word that proceeds from the mouth of God.’ ” Then the devil took Him up into the holy city, set Him on the pinnacle of the temple, and said to Him, “If You are the Son of God, throw Yourself down. For it is written: ‘He shall give His angels charge over you,’ and, ‘In their hands they shall bear you up, Lest you dash your foot against a stone.’ ” Jesus said to him, “It is written again, ‘You shall not tempt the Lord your God.’ ” Again, the devil took Him up on an exceedingly high mountain, and showed Him all the kingdoms of the world and their glory. And he said to Him, “All these things I will give You if You will fall down and worship me.” Then Jesus said to him, “Away with you, Satan! For it is written, ‘You shall worship the Lord your God, and Him only you shall serve.’ ” Then the devil left Him, and behold, angels came and ministered to Him.

Taking the place of Barabbas: 
Will continue into Chapter 2 of "The living sacrifice."

Lord, how are they increased that trouble me! many are they that rise up against me. Many there be which say of my soul, There is no help for him in God. Selah. But thou, O Lord, art a shield for me; my glory, and the lifter up of mine head. I cried unto the Lord with my voice, and he heard me out of his holy hill. Selah. I laid me down and slept; I awaked; for the Lord sustained me. I will not be afraid of ten thousands of people, that have set themselves against me round about. Arise, O Lord; save me, O my God: for thou hast smitten all mine enemies upon the cheek bone; thou hast broken the teeth of the ungodly. Salvation belongeth unto the Lord : thy blessing is upon thy people. Selah. (Psalms 3:1-8 KJV)