Since that was in my post, I will offer the scriptural basis for it.
Galatians 3:13...
"Christ purchased us, releasing us from the curse of the Law by becoming a curse instead of us, because it is written: “Accursed is every man hung upon a stake." (Deuteronomy 21:33)
Christ's sacrifice paid a price...the price that was set by God's law.
Matthew 20:28...
"Just as the Son of man came, not to be ministered to, but to minister and to give his life as a ransom [Greek, lyʹtron] in exchange for many.”
"lyʹtron" is "the price for redeeming, ransom", according to Strongs.
What is a ransom?
If a kidnapper demanded a ransom for the return of the one they took captive, the price set by the kidnapper would be in accordance with what they believed the kidnapped person was worth.
Since God's redemption law was to pay a set price for what was to be redeemed, the debtor could not offer less and they would never have offered more.
God's law stated "an eye for an eye, a tooth for a tooth and a life for a life" (literally "soul for soul") (Deuteronomy 19:21)
As an example Exodus 21:28-32 speaks about a bull that gores a person to death. If the owner knew of the bull’s disposition but did not take proper precautions, he could be made to pay, for the life of the one killed, with his own! Yet, what if the owner was only partially responsible? He would still need to provide compensation for the person's death. Appointed judges could impose a ransom, or fine, as a redemption price.
The man who paid the ransom for the human race had to be a perfect human of flesh and blood—the exact equal of Adam. (Romans 5:14) A spirit creature or a “God-man” would not balance the scales of justice. Only a perfect human, someone who was not under the Adamic death sentence, could offer “a corresponding ransom,” one corresponding perfectly to Adam. (1 Timothy 2:6) The Greek word here used, an·tiʹly·tron, appears nowhere else in the Bible. It is related to the word that Jesus used for ransom (lyʹtron) at Mark 10:45.
The New International Dictionary of New Testament Theology points out that an·tiʹly·tron ‘accentuates the notion of exchange.’
By voluntarily sacrificing his life, this “last Adam” could pay the wage for the sin of the “first man Adam.”(1 Corinthians 15:45; Romans 6:23)
Incidentally, did you know that Adam is identified as "a son of God"? (Luke 3:38) He rightly held that title because he was a direct creation of God...perfect in every way. There was no defect of sin in him until he disobeyed his Creator.