We have all sinned in transgression to God’s law. It was simultaneously an act of God’s justice and grace where Jesus takes our place, and fulfills the righteousness of the law. To make the sacrifice possible. Receiving the full measure of its condemnation against sin, which is death; and therefore, paying the price for our salvation with His own blood as a sacrifice for sin.
As a result of His sacrifice, we could only be justified by faith in His sacrifice, and by faith in His Sacrifice no longer choose to live in transgression to keep God’s commandments.
The law could only be kept by faith in response to God’s love, and out of love to God, because of His grace through His Son Jesus Christ.
To then not keep the law is to live in transgression. And to live in transgression is to deny the free gift of God’s love by faith. This demonstrates to keep the law is only out of faith in a profound love and appreciation for His love for us. Due to His grace through the sacrifice of His Son.