In Mark 12:28-34, a teacher of the law came to Jesus and asked Him, "Of all the commandments, which is the most important?" Jesus responded by quoting from Deuteronomy 6:4-5 and Leviticus 19:18. The first of these is that we are to love the LORD our God with all our heart and with our soul and with all our might. Why is the LORD to be the object of our love? There are many, many reasons why we must love our LORD God, but I would like to list three based on who and what He is.
First, we must love our God, because our God is our Creator, who created us in His image. Bearing His image demonstrates whom we belong to. In Matthew 22:15-22, some Pharisees and Herodians tested Jesus by asking whether they should pay taxes to the Caesar. Jesus asked to see a coin and asked whose image and inscription the coin had. He then said to give to Caesar what is Caesar's. Bearing the Caesar's image demonstrated that the tax money belonged to him; bearing God's image demonstrates that we belong to God.
Furthermore, bearing His image demonstrates that God considers us extra special among all creation. There is no other creature that was created in His image. When God created man, He breathed into him to make him a living soul. There is nothing else mentioned in the Scripture into which/whom God breathed, other than the Scripture itself (II Tim 3:16) and man (Genesis 2:7). God considers us so special that "even the hairs of your head are all numbered" (Matthew 10:30), He has engraved us on the palms of His hands (Isaiah 49:16), and He will rejoice over us with gladness ... and exult over us with loud singing (Zephaniah 3:17). God made us to rule over all the earth and all the creatures (Genesis 2:26).
Now since Jesus is the "exact imprint of God's nature" (Hebrews 1:3), the fact that we are created in God's image means that we are created in Jesus' likeness. In a way, we are Jesus' kind. Therefore, Jesus is not ashamed to call us His brothers (Hebrews 2:11). He even calls us to be His bride (Ephesians 5:22-33), His "flesh of flesh and bone of bones." Note that God's mating principle (i.e., who can be a husband and a wife) is that they mate among the same kind (Genesis 7; Leviticus 19:19). That Jesus considers us, His church, a worthy bride of His means that He considers us to bear His image and His likeness and therefore to be His kind. How wonderful and how mysterious!
Second, we must love God, because He is our Savior, who is also our Salvation. When we are saved and receive salvation, what is it exactly that we receive? Is it forgiveness of our sin, entry to the heavenly kingdom of God, or eternal life? Yes, in a way. Salvation does include forgiveness of sins, citizenship in the kingdom of heaven and eternal life. But salvation is much more than that. The Bible says that our LORD is Salvation (Exodus 15:2, Psalm 42:5,11, 43:5, 68:19, Isaiah 12:2, etc.) In Ephesians 2:8, it says that we have received salvation through faith by grace -- this is a gift from God. I think grace is a gift, faith is a gift, and so is salvation. The greatest gift that God wants to give to us is Himself, who is our Salvation. In Luke 11:13, Jesus says, "If you then, who are evil, know how to give good gifts to your children, how much more will the heavenly Father give the Holy Spirit to those who ask Him?" The best gift we can ask our Heavenly Father for is Himself. He Himself is the object of our yearning, of our want, and of our love.
Only then, can we confess with David that "the LORD is my shepherd; I shall not want" (Psalm 23:1). Or with Asaph that "Whom have I in heaven but You? And there is nothing on earth that I desire besides You." (Psalm 73:25). When we have God, we (should) have all that we desire. When we have God, all other good things follow; yet, it should not be because of all other good things that follow that we desire God. We should desire and love God, because He Himself is the object of our yearning and of our love. Our God who did not spare His own Son for us will not spare anything else, either (Romans 8:32).
In John 4, we read about a Samaritan woman who met Jesus at the well in Sychar. She had had 5 husbands and the man she was living with was not her husband. Even though she had had 6 men, her thirst was not quenched. She had a void, was in darkness and in disarray. She was like the world, before God said, "Let there be light" (Genesis 1:2). Then the light of God shone on the world to drive away the formlessness, darkness and emptiness (John 1:1-18). Jesus is the light and the giver of the living water that flows eternally. Jesus is our Salvation and the object of our love.
Third, we must love God, because He is a triune God who wants the same loving relationship that exists among the three Persons of Godhead to exist between Himself and us. In John 17, Jesus offered a priestly prayer for his disciples -- not only the 12 Apostles, but also all those who would come to believe in Him through their word (John 17:20). Jesus prayed, "... that they may all be one, just as you, Father, are in Me, and I in You, that they also may be in us, so that the world may believe that you have sent me. The glory that You have given Me I have given to them, that they may be one even as We are one, I in them and You in Me, that they may become perfectly one, so that the world may know that You sent Me and loved them even as You loved Me." (John 17:21-23). Jesus prayed that we may be one just as the Father and the Son are one. Jesus said that the Father loved us even as He loved the Son. Wow! What an incomprehensible love that God has bestowed upon us! God has loved us even as He loved His only-begotten Son! It is only right that we love Him in kind.
"God the Father, God the Son, God the Holy Spirit! I love You with all my heart, with all my soul, with all my strength, and with all my life. I love You and yearn for Your Presence in all of me. Fill me with Your Spirit. Dwell in me and empower me, so that all that I am and do may be in Christ Jesus and for Your glory. I pray in Jesus' Name. Amen."