Isaiah 6:3

Isaiah 6:3 is the seraphim's threefold cry of God's holiness, the central worship-word of the entire vision. To call something "holy" in Hebrew is to set it apart, utterly distinct and pure. Repeating the word three times is the strongest emphasis the language allows -- not merely holy, but holy beyond all comparison, holy in the supreme degree.

The title "LORD of hosts" pictures God as commander over the armies of heaven, sovereign over all powers seen and unseen. Yet the cry does not stop at His transcendence; it declares that "the whole earth is full of his glory." The God who is so set apart that even angels veil themselves is also the God whose splendor saturates creation. Heaven sees what earth often misses -- that every corner of the world already brims with the weight of His presence. This is worship answering worship, one seraph calling to another, an unending exchange of praise. For Isaiah, hearing it will expose his own uncleanness in the very next verses. For the reader, it sets the pattern of all true worship: beginning not with our needs but with the staggering holiness of God, and ending in wonder that such glory fills the earth we walk.