The central message of this sermon is that while fearing God and keeping his commandments is essential for a man's duty, it is insufficient on its own; true fulfillment and purpose in life come from loving God with all one's heart, soul, and mind. The sermon advances the belief that mere obedience to God's commands without a genuine love and relationship with Him leads to emptiness and meaninglessness, as exemplified by King Solomon's life. The takeaway is that Christians should not be content with simply following rules or moral codes, but rather cultivate a deep and intimate love for God, which will naturally lead them to obey His commandments out of devotion and joy, rather than mere duty.