I can remember the moment when each of my kids let go of the coffee table to take steps for the very first time. In letting go of the table they looked at me and then raised their hands towards me. It's one of those feelings that never gets old, my heart was full of love. God instructs us to reach out our arms toward Him in worship. I can't be for sure, but I feel like one reason is because God loves it, it's one way we can show our dependence on Him.