Charles Spurgeon Commentary Isaiah 6:3-4

"And one cried unto another, and said, Holy, holy, holy, is Jehovah of hosts: the whole earth is full of his glory. And the foundations of the thresholds shook at the voice of him that cried, and the house was filled with smoke." — Isaiah 6:3-4 (ASV)

And one cried upon another, and said, Holy, holy, holy, is the LORD of hosts: the whole earth is full of his glory. And the posts of the door moved at the voice of him that cried, and the house was filled with smoke.

And if even the voice of a seraph moved the very foundations of the temple, what will the voice of God do when he speaks once more? According to that word, he shall shake not only earth, but also heaven. What awe and trembling should be on us when we wait on God, if even the posts of the door move! Then said I, Woe is me! All God's saints do this when they get a view of him.

There was never a boastful thought in any man's mind in the presence of God. Those who talk of their own purity have not known God, nor seen him. How could they! This is the cry of all the purified when they come into the presence of God: Woe is me, for I am undone; because I am a man of unclean lips.

What made him think of lips, but the voice of the seraphim as they cried responsively to one another, Holy, holy, holy? Then he thought of his own lips. Oh! brothers and sisters, what impurity comes out of our lips! Perhaps it is there, more than anywhere else, that the impurity of the heart is discovered in our idle words, our evil words.