Perhaps you’ve heard a pastor talk about “the great exchange”– the way that Jesus took our place, died for our sins and reconciled us with God. In return, we received His righteousness. When God looks at us, he no longer sees our sins and failures, He see Jesus. I came across this quote by John Stott recently, which describes this process so succinctly.
“The concept of substitution may be said, then to lie at the heart of both sin and salvation. For the essence of sin is man substituting himself for God, while the essence of salvation is God substituting himself for man. Man asserts himself against God and puts himself where only God deserves to be. Man claims prerogatives which belong to God alone; God accepts penalties which belong to man alone.”
From The Cross of Christ by John Stott
Although I was familiar with the idea that Jesus took our place, receiving the punishment , I never stopped to think about what caused the sin that made it necessary. It all starts with man trying to usurp God’s place. That is, indeed, the essence of sin and we do it every day in different ways. Reminding ourselves of what our sin is, and what it cost, is the beginning of wisdom.

For more about John Stott, see these posts: