"The law of God is in his heart; none of his steps shall slip." Ps. 37:31

In this 37th Psalm David is contrasting the conduct of the righteous man versus the wicked man. Something is in the heart of the righteous that is not found in the heart of the wicked. That something is the law (words) of God. The word "law" here would include all of God’s instructions, as well as the 10 Commandments. Slipping and falling can cause serious debilitating injuries, if not death. A spiritual slipping and falling away from the Lord can have devastating consequences to the life of a believer. When the Word of God is our heart, nurtured and cherished, our choices will be directed by the truth of God; and our steps will not slip. Without the word of God life is a slippery slope.