"But seek ye first the kingdom of God, and his righteousness; all these things shall be added unto you," (cf. Matt. 6:33).
"In whom the god of this world hath blinded the minds of them which believe not..." (cf. 2 Cor. 4:4).
The First Commandment is the greatest and summation of all God requires of us. All others are mere corollaries and applications. If we have God, we have all we need! In antiquity, they were thinking that the more gods you had, the better off you were! They had a whole pantheon of gods and failed to realize the Most High. But if we have God, we have all we need. We all can have insecurities, but where we find it is vital to our salvation and obedience to God. We can get obsessed with the wrong priorities in life and must realize how idolatrous we are and make honest confession to God to be cleansed of it--coming clean! God must not be replaced as the owner of our heart and our first love. God is greater than any idol can ever be; if we worship them, we are the loser: We forfeit the grace that could be ours!
If we fail to admit it, we are only cheating ourselves. We must not sacrifice temporary happiness or fulfillment for the permanent one found in Christ. We must live in light of eternity, not just for the here and now. We are to be content only in God. God is greater than our heart and we must realize the battle is the LORD's and submit to His authority over our lives. Those who "know their God shall be strong and do exploits" (cf. Dan. 11:32). So we must have a handle on who God is and His role in our lives. With God, we can confront evil and realize how great He is in our lives. Remember, God called Abraham out of idolatry and so we must come out from it; it's the default state!
We can only defeat our idols in the name of the Lord and victory through the Spirit who sets us free from the lies of Satan. Sin holds us in bondage and alienates us from God. This may entail sacrificing temporary happiness for the long term fulfillment of God's will. The joys of this world pass away but that of the Spirit endures. One way to sacrifice this is by being people-pleasers instead of seeking the praise that comes only from God. God is greater than all our idols. It is only the truth that sets us free and God is the one who grants repentance leading to the knowledge of the truth. Those who love the truth are saved and those who suppress it are condemned.
When we give God His place of honor and reverence, we are only giving Him what we owe Him and can never pay back--an eternal debt of gratitude and worship. We can march on in victory with God on our side with the marching orders to spread the word. We can navigate our mission in the name of the Lord and not in our name or of any idol. God holds our allegiance only and no one else. We do not say my affiliation right or wrong, whether it be party, church, race, or state. Then we are on solid ground and firmly planted into God's will--the safest place to be.
But we must all come to a confrontation with evil and not waver between the two opinions of wondering who God is and whom we will serve. All idolatry is ultimately a betrayal of the one whom we owe allegiance to and becoming a two-timer with God or cheating on Him and not being faithful. Sooner or later, God will teach us that there is but one God who is worthy of our worship and allegiance.
Thus, the First Commandment reminds us of who God is and who we are in perspective, and our duty to Him as our Number One priority. God must be in the first place or He has no part of us. He will not settle for a second-place or lower status in our hearts. He wants us to have the spiritual wake-up call and realize: "The LORD, He is God!" Soli Deo Gloria!