Greetings Ran77,
I am happy with blings explanations in Posts #2 and #7. I agree with Norah63 in Post #13, but with the condition that the effect of contact with Christ, our altar of burnt offering, is not instantaneous and full. In other words our contact with Christ is a slow transforming process.
I find Isaiah 6 fascinating, as it is a vision, but Isaiah interacts in a very realistic way, as if he is transported into the vision. Concerning the concept of unclean lips, the context is important. Isaiah had denounced the nation as being sick in Isaiah 1, but here he recognises his own uncleanness, as well as the people. Also the context is the death of Uzziah, and he had been smitten with leprosy when he had in pride entered the Temple, having taken a coal with incense in a censer. Now Isaiah was given a vision into the Temple, and he was fearful, and greatly humbled by the holiness of the vision, recognising his own inadequacy. One of the requirements of a leper was to cover his upper lip, a symbol of uncleanness, and Isaiah is confessing this condition in a spiritual sense, both for himself and his people.
Isaiah 1:4-5 (KJV): 4 Ah sinful nation, a people laden with iniquity, a seed of evildoers, children that are corrupters: they have forsaken the LORD, they have provoked the Holy One of Israel unto anger, they are gone away backward. 5 Why should ye be stricken any more? ye will revolt more and more: the whole head is sick, and the whole heart faint.
Isaiah 6:1 (KJV): In the year that king Uzziah died I saw also the Lord sitting upon a throne, high and lifted up, and his train filled the temple.
Isaiah 6:5-8 (KJV): 5 Then said I, Woe is me! for I am undone; because I am a man of unclean lips, and I dwell in the midst of a people of unclean lips: for mine eyes have seen the King, the LORD of hosts. 6 Then flew one of the seraphims unto me, having a live coal in his hand, which he had taken with the tongs from off the altar: 7 And he laid it upon my mouth, and said, Lo, this hath touched thy lips; and thine iniquity is taken away, and thy sin purged. 8 Also I heard the voice of the Lord, saying, Whom shall I send, and who will go for us? Then said I, Here am I; send me.
Thus the vision uses typical things, such as the Temple, a coal from the altar, the concept of clean and unclean lips of the leper, to depict spiritual lessons, and effect the commissioning Of Isaiah to preach as in verse 8.
Kind regards
Trevor