I found today's reading fascinating. And with reading the footnotes in the Orthodox Study Bible I learned some new things.
In the year King Uzziah died, I saw the Lord sitting on a throne, high and lifted up. The house was full of His glory. Around Him stood seraphim; each one had six wings: with two he covered his face, with two he covered his feet, and with two he flew. And one cried to another and said, "Holy, holy, holy is the Lord of hosts; the whole earth is full of His glory." The lintel was lifted up by the voice of those who cried out, and the house was filled with smoke. So I said, "Woe is me, because I am pierced to the heart, for being a man and having unclean lips, I dwell in the midst of a people with unclean lips; for I saw the King, the Lord of hosts, with my eyes!" Then one of the seraphim was sent to me. he had a live coal in his hand, which he took with tongs from the altar. He touched my mouth, and said, "Behold, this has touched your lips. Your lawlessness is taken away, and your sin is cleansed." Isaiah 6:1-7 (today's reading was actually through verse 12)
Footnote: Isaiah's vision has strongly influenced the development of Orthodox Christian worship. For the Church, like heaven, has an altar, a throne, smoke from the incense, and believers singing "Holy, holy, holy," the thrice Holy hymn.
Footnote: A live coal touching the mouth: Isaiah experiences a symbol of the Eucharist, which is taken from the altar to be served to the faithful. In fact, after an Orthodox priest receives communion, he quietly quotes the seraphim's proclamation.(v.7)