Lets look at this.
1. The penalty of sin is death,
2. We are born dead in adam,
3. We are made alive who were dead....
conclusion.
spiritual death (separation from God) is the penalty of sin.
Jesus, on the cross. Said it is finished (tetelestai)
Tetelestai in the Greek is actually a judicial term. It means "paid in full"
Jesus in his own words states the penalty of sin was paid in full. Yet he had not yet died physically yet. He also then let his physical body die a physical death.
While on the cross. And while getting beat, He never cried out. Not once did he cry out. Until the 9th hour. something so horrible in that moment made his scream in pain.
what was that thing that made him scream?
Your sin, My sin, The sin of the whole world was placed on his body, and in that moment, He suffered the penalty of sin (spiritual death) as he screamed, My God (father) My God (Holy Spirit) Why have you forsaken me.
Forsake in greek - enkatelipes - to abandon, to desert, to leave behind, to forsake,
so yeah.. Not only is it scripturally. but it is right there in black and white.
Christ became a curse for us.
Subsitituion.
Christ died for us - substitution
he who knew no sin, became sin, substitution.
Without substitution there is no satisfaction.
As for Christ paying a price. He redeemed (purchased) us by his blood. that was the price.