“Christ has redeemed us from the curse of the law, having become a curse for us (for it is written, ‘Cursed is everyone who hangs on a tree’), that the blessing of Abraham might come upon the Gentiles in Christ Jesus, that we might receive the promise of the Spirit through faith” (Galatians 3:13-14).
In explaining how “Christ has redeemed us from the curse of the law” Galatians 3:13 refers to the important Biblical concept of redemption. For many, the idea of “redemption” is often synonymous with a type of transfer or exchange. For instance, a person who takes part in a consumer rewards program will often receive points or credits that he or she may redeem (or exchange) for something of value.
However, a closer look at the original language of this verse reveals that the word “redeemed” carries a more expansive definition: “(The) payment of a price to recover from the power of another, (or) to ransom, buy off.” (1) Another source clarifies this idea in addressing the question of how Christ redeemed humanity…
“The answer is by becoming a curse for us. This is a strong declaration of substitutionary redemption whereby Christ took the penalty of all guilty lawbreakers on Himself. Thus the ‘curse of the Law’ was transferred from sinners to Christ, the sinless One (cf. 1Pe_3:18), and He delivered people from it.
The confirming quotation from Deu_21:23 refers to the fact that in Old Testament times criminals were executed (normally by stoning) and then displayed on a stake or post to show God’s divine rejection. When Christ was crucified, it was evidence He had come under the curse of God. The manner of His death was a great obstacle to faith for Jews until they realized the curse He bore was for them (cf. Isa_53:1-12).” [bkc]
So Jesus’ death on the cross ransomed (or recovered) us from our state of separation from God. As our judicial substitute, Jesus delivered humanity from the judgment associated with a Law we could never completely fulfill. To put it another way, “…Christ has redeemed us from the curse of the Law’s condemnation, by himself becoming a curse for us when he was crucified” (Phillips).
However, this does not mean that the Old Testament Law holds no further importance. On the contrary, the Mosaic Law holds a great deal of value as the latter portion of this chapter will demonstrate. Nevertheless, it does mean that the Law cannot ultimately redeem those who follow it- only Christ’s substitutionary atonement could accomplish that.
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(1) G1805 exagorazo https://www.blueletterbible.org/lang/lexicon/lexicon.cfm?t=kjv&strongs=g1805
(2) John F. Walvoord and Roy B. Zuck, Bible Knowledge Commentary [p.598]