I ran into an interesting passage today:
Truly no man can ransom another, or give to God the price of his life, for the ransom of their life is costly and can never suffice, that he should live on forever and never see the pit. (Psalm 49:7-9)
If we wanted to save someone from the wrath of God, we could not simply give up ourselves. We couldn't say to God, "God, save my friend. I'll go to hell in his place." Why? We couldn't afford it. The price to save the other's life is too much, and our own life is not valuable enough. Apart from Christ, we are worthless. We are therefore unworthy to pay the ransom for someone else.
The psalmist's hope is in verse 15: "But God will ransom my soul from the power of Sheol, for he will receive me."
God would pay the ransom for the psalmist. But how would He pay the ransom? By giving up the life of His only Son.
The beauty of Christ, the God-man, is that not only could He ransom one person, but His worth was enough to ransom all of His people. Every single person for whom Christ died has been purchased by His own blood. So, we sing, "This I know with all my heart: His wounds have paid my ransom" (How Deep the Father's Love For Us).
Christ paid the ultimate price, and it was worth all of the souls for whom He died. He ransomed us, because no one else could. Praise God!