Despite what Paul says, I don’t think God desires us to be slaves of God.
God does not deliver us from bondage only to re-enslave us, because that would simply be putting new wine into old wineskins. God wants us to be free, to flourish, to be the healthy, vibrant people God created us to be. Being captive to God would only be marginally better than being captive to wealth or sex or drugs or other people, because in any of those circumstances we become something less-than-human in the world – and sometimes we even become less-than-human to ourselves. God wants us to be complete, whole, fulfilled. Human.
When God guides us, we aren’t expected to follow blindly, obeying simply because we read a command in the Bible; rather, God expects us to see God’s heart for us, to discern the value of living in authentic community, and to understand the depth and richness of loving ourselves and loving our neighbors, encouraging in them the same flourishing God encourages in us.
God is not a slave lord seeking domination or praise; God is a proud, loving parent who wants to see us thrive. We love God not because God commands it, but because God is love, has loved us deeply since before we took our first breaths, and shows us how to radiate love back into the world.