In school you learn at an early age about addition and subtraction. They go together; they are opposites. Once you get a bit older you learn about adding negative numbers. That’s subtraction right? 4-2=2 and 4+(-2)=2.
To subtract something, you add it’s opposite. To subtract 2 from 4 above, we added the opposite of 2 which is -2. If you want to subtract sin from your life what can you add? What is the opposite of sin?
The opposite of a sinful life is a righteous life. Sin is something against God’s law, righteousness is following His law. To subtract sin from our lives, Christ’s righteousness needs to be added.
John 1:29 says “The next day he saw Jesus coming toward him, and said, “Behold, the Lamb of God, who takes away the sin of the world!”
In Romans 3:23-24 we read, “for all have sinned and fall short of the glory of God, and are justified by his grace as a gift, through the redemption that is in Christ Jesus,”
The redemption is Jesus subtracting our sin, by adding His righteousness.