Isaiah's encounter with God's presence

Isaiah is brought into the throne room of God in the year that King Uzziah died. He is confronted with the immense glory and holiness of God, as depicted by angelic beings called seraphim. Isaiah is overwhelmed by his own unworthiness and confesses that he has unclean lips, not only for himself but for his people as well. Instead of going through complex rituals and purification ceremonies, God, in His grace and mercy, provides a burning coal that purifies Isaiah's lips and forgives his sins. Through this divine encounter, Isaiah is commissioned as a prophet and receives the assurance that his guilt is taken away.