The call to separate from sin should be dealt with immediately. The call to obey his word must not be ignored. We should learn from watching what is going on around us, especially in the lives of our relations. The sins and punishments of others should be a warning to us. The righteousness and blessings of others should be an encouragement to us to follow the ways of righteousness.
Sin starts in the heart.
It is in the heart that we say the small things do not matter. Their hardness against God's voice, v. 7, provoked the Lord, and caused them to miss the blessings of God. The hardening of the heart to the call of God, the word of God, is the spring of all sins. As we ignore him in the small things, we soon ignore him in the large things. 19 Who being past feeling have given themselves over unto lasciviousness, to work all uncleanness with greediness.