In him we have redemption through his blood, the forgiveness of sins, in accordance with the riches of God's grace. (Ephesians 1:7, NIV)

He is so rich in kindness and grace that he purchased our freedom with the blood of his Son and forgave our sins. (Ephesians 1:7, NLT)

You belong to your father, the devil, and you want to carry out your father's desires. (John 8:44, NIV)

Oxford definition of Redeem

Save (someone) from sin, error, or evil

Gain or regain possession of (something) in exchange for payment

Pay the necessary money to clear (a debt)

Free (oneself or another) from slavery or captivity by paying a ransom

From Wikipedia on Redeemer

In Christian theology, Jesus is sometimes referred to as a Redeemer. This refers to the salvation he is believed to have accomplished, and is based on the metaphor of redemption, or "buying back". Although the Gospels do not use the title "Redeemer", the word "redemption" is used in several of Paul's letters. Leon Morris says that "Paul uses the concept of redemption primarily to speak of the saving significance of the death of Christ." The English word redemption means 'repurchase' or 'buy back', and in the Old Testament referred to the ransom of slaves (Exodus 21:8). In the New Testament the redemption word group is used to refer both to deliverance from sin and freedom from captivity.

What I understood from above sources is that once we were the property of God but because of Adam and Eve, we are now the property of Satan or Sin. Now Jesus offered his blood to buy us back from the hands of Satan/Sin. What I don't understand here is why Jesus had to pay the price. If God is all powerful, He should be able to rescue us from the slavery of Satan/Sin, without the need to pay anything. Why did Jesus have to pay the price? Is it because

  1. God cannot rescue us from Satan/Sin forcefully because Satan is almost as powerful as God. For instance, US cannot simply go and take back the American prisoners in Afghanistan forcefully. There must be some negotiations or the ransom paid.
  2. There is some kind of Universal Law that God cannot violate, that a sinless one must die for the sinners.
  3. God had made a Law that a sinner must go to Hell and He cannot violate it or doesn't want to. Hence, God sent His Son to pay the price in order to satisfy Himself.
  • The question Why did Jesus have to die? has lots of discussion on what I think is the same subject you're asking about. – kuzzooroo Mar 15 '15 at 23:54
  • This scripture might help explain (Even if you don't believe the Book of Mormon, I think it does a good job of explaining the idea.) Alma 42:15 "And now, the plan of mercy could not be brought about except an atonement should be made; therefore God himself atoneth for the sins of the world, to bring about the plan of mercy, to appease the demands of justice, that God might be a perfect, just God, and a merciful God also." – Drew LeSueur Dec 10 '17 at 18:54