The need for Jesus to offer Himself as a sacrifice for us started right at the beginning. The bible says that God created a perfect place. He created living things, then man and woman. Then He gave man free will. He gave them instructions not to eat of a certain tree, or they would surely die. Eve was tempted, she ate, she offered the fruit of that tree to Adam as well, they died.
They didn't die physically right away. The bible says they lived several hundred more years. But they died spiritually. They could no longer walk with God in the cool of the day as they once had. They could no longer have relationship with Him.
God found them hiding, fearful. It was then that the first sacrifice took place. God killed an animal and covered them with its skin. That sacrifice enabled them to commune with God for a little while.
From that time onward anyone who wanted to have relationship with God first had to offer a blood sacrifice. This is because in Adam's fall he and all the generations after him were cursed. They were dead, spiritually. But if something else took that death, then for a little while, they could have relationship with God.
Every patriarch offered sacrifices. Noah did. Job did. Abraham did. When the Hebrews were called out of Egypt God gave instructions to Moses, and the Levitical priesthood and systematic sacrifice were established. The bible says that without the shedding of blood there is no forgiveness, "for it is the blood that makes atonement for your soul," Leviticus 17:11. "And according to the law almost all things are purified with the blood, and without shedding of blood there is no remission," Hebrews 9:22.
This system of sacrifice served to make atonement for millions of people over a period of more than 1,400 years, but it was faulty. It depended on animal sacrifice. It could only cover sin, it could not forgive sin, Hebrews 10:4, "For it is not possible that the blood of bulls and goats could take away sins." It also had to be repeated daily, weekly, monthly.
Something better had to come. God knew what that something better was. In all the Levitical sacrifices and before, a sacrificial animal had to be perfect. God had something perfect. He sent His own Son. This is why when John the Baptist first saw Jesus he said, "Behold the Lamb of God," John 1:36.
Jesus became the final sacrifice. It is not possible for there to have been any other way, because the sacrifice had to be perfect. The bible says that we all have sinned and fallen short of the glory of God, Romans 3:23, and that the wages of sin is death, Romans 6:23. When Adam and Eve sinned, they died. We sin, we die. But there is a way for the penalty of death to be taken by Jesus, because He was perfect. The bible says that although He was tempted He never sinned, Hebrews 4:15.
Because of the fall we live in a cursed world, Romans 8:21; Gen. 3:17. Because of the fall we are dead in our trespasses and sins, Romans 3:23. But God has provided us a way out.
His name is Jesus. He is the way out. He offers an exchange. Give Him your life, and He will give you His life. Ask Him to forgive you, and you be cleansed by His atoning blood. Present yourself to Him, and He will never cast you out. He will never leave you or forsake you, Hebrews 13:5. He will be with you always, and you will be with Him in eternity.
God gave free will. The ability to choose is never taken away from us. It is up to us to live for Him or not, to go on with Him, to allow Him to make each of us into the son or daughter He desires us to be--cleansed, victorious, freed from the bondages of sin and death. But it is also up to us to choose.