Archbishop Fulton J. Sheen wrote a wonderful little book called You, which is really about us and our relationship with God. Although the cultural references are a little dated, here is a cursory explanation, sprinkled with golden nuggets of insight, of why we worship God.
If you are a father, do you not like to receive a tiny little gift, such as a penny chocolate cigar, from your son? Why do you value it more than a box [of cigars] from your insurance agent? If you are a mother, does not your heart find greater joy in a handful of yellow dandelions from your little daughter, than a bouquet of roses from a dinner guest? Do these little trivialities make you richer? Would you be imperfect without them? They are absolutely of no utility to you! And yet you love them. And why? Because by these gifts your children are “worshipping” you; they acknowledge your love, your goodness, and by doing so they are perfecting themselves; that is, they are developing along the lines of love rather hate, thankfulness rather than ingratitude, and therefore they are becoming more perfect children and happier children as well.
As you do not need dandelions and chocolate cigars, neither does God need your worship. But if their giving is a sign of your worth in your children’s eyes, then is not prayer, adoration, and worship a sign of God’s worth in our eyes? And if you do not need your children’s worship, why do you think God needs yours? But if the worship of your children is for perfection, not yours, then may not your worship of God be not for His perfection, but yours? Worship is your opportunity to express devotion, dependence, and love, and in doing that you make yourself happy.
…God would still be perfectly happy if you never existed. God has no need of your love, for there is nothing in you, of and by yourself, which makes you lovable to God. Most of us are fortunate to have even a spark of affection from our fellow creatures. God does not love us for the same reason that we love others. We love others because of need and incompleteness. But God does not love us because He needs us. He loves us because He put some of His love in us. God does not love us because we are valuable; we are valuable because He loves us.
…Without Him, you are imperfect; but without you, He is still Perfect. It is the echo that needs the Voice, and not the Voice that needs the echo. …God thirsts for your love, not because you are His waters of everlasting life, but because you thirst, He is the waters. He needs you only because you need Him.
It is always about the other. By giving yourself to others in some form or another, you receive and are transformed. The cycle of love continues to flow. All is gift…receive, share, and give thanks.