The apostle gives this warning directly to God's children. Despite how we may personally relate to Him in how we live, God cannot deny what He truly is. We may be highly variable in our attitude and conduct because we are lackadaisical and tolerate human nature having its way. We may yield to this world's influence on us and backslide into the same careless way of life that dominated us before God called us into His church (Ephesians 2:3). Yet, our God and Savior is constant and faithful to what He is. His character and purpose never change. God loves, and because He does, He also judges. Does not Proverbs 13:24 instruct, "He who spares his rod hates his son, but he who loves him disciplines him promptly"? Our Savior will not overlook this need in us.
Sometimes His discipline can be very stressful (Hebrews 12:11), but that is the cost of following Him where He leads. He will act as He truly is regardless of what we personally think or fail to think or whether we allow Him to be closely or only marginally involved in how we live our lives.
This world's nominal Christianity has so wrongly overemphasized God's grace that it makes salvation assured if we will only accept Jesus Christ. However, it does so without equally teaching that we must meet the responsibilities that God also clearly reveals. We must faithfully walk to the Promised Land. To keep our part of the New Covenant, we must live His way of life to be prepared to live in the Promised Land.