My friend recently built a big farm table for his family. He designed the table, he bought all the wood, and he sanded every part of the table and put a beautiful dark wood stain to finish it off. He worked diligently all summer on this table with the hopes that the finished product would be perfect so that it would last for generations. He did all the work.
Now let’s say I go over to his house and pick up a piece of sandpaper to add one stroke to the table. As I approach the table, my friend yells out, “No!! It is finished. To add anything to it would subtract from it.” It would be foolish of me to think that I could add anything or to improve upon the finished work. Similarly, it would be foolish to try to add anything or to improve upon the finished work of our salvation. On the cross, Jesus yelled out, “It is finished.” Salvation was completed for those who would trust in the finished work of the cross.
We cannot save ourselves. We cannot add anything to the work that God has finished for us through Jesus Christ. We are justified by faith in Christ and not by our works of righteousness. As Tim Keller points out, if we believe that our work in any way saves us then we shift from believing in Jesus Christ as our Savior and turn to believing in ourselves as our savior. Jesus Christ does not get us all the way up to the finish line and then our works push us over the edge. Jesus Christ carries us through the finish line of our salvation. It is finished.
Beloved, do not try to add or subtract anything from God’s great work of redemption. We are “justified by his grace as a gift through the redemption that is in Christ Jesus whom God put forward as a propitiation by his blood, to be received by faith (Rom. 3:24-25).” Receive your salvation from Christ by faith. Do not try to be your own savior. Trust in the words of Jesus, “It is finished.”
 Adapted from an illustration shared by Tim Keller.
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