Even though we cannot see it or touch it, heaven is as real and vital to us in our worship as oxygen is to our respiration. In fact, worship is a kind of spiritual respiration. We breathe air into our lungs that we cannot see — and we live. In the same way, as we worship we breathe heaven into our souls — and we live, filling our hearts with the unseen, life-giving atmosphere of heaven. Thus, worship requires faith, for “faith is the assurance of things hoped for, the conviction of things not seen” (Heb. 11:1). Faith convinces us that we are in the realm of heaven as we worship, and it encourages us to breathe deeply, that we might become more fully alive.