What does Psalm 103:9 mean?

Following his description of the Lord as merciful, gracious, slow to anger, and abounding in steadfast love, David writes that God does not always "chide." The Hebrew word here is yā'rib, which implies a legal argument, accusation, or debate. God does not perpetually bring a court case against us. He certainly has enough evidence to condemn us, but He refuses to do so. He has a right to be angry with us, but He forgoes that right.

How do we, living so long after Israel, know that God is loving and merciful, even to sinners? The answer is Jesus, who took the punishment for our sins. On the cross he was made sin for us "so that in him we might become the righteousness of God" (2 Corinthians 5:21). The prophet Isaiah predicted the sufferings of Jesus on our behalf. He wrote in Isaiah 53:6, "All we like sheep have gone astray; we have turned—every one—to his own way; and the LORD has laid on him the iniquity of us all."