The purpose for which it was required on this occasion was cleansing. Of cleansing there are in Scripture three symbols. The simplest is water; and water can purify many things; but there are some things which water cannot cleanse. A stronger agent is required, and this is found in fire. You must fling the ore, for example, into the fire, if you wish to extract from it the pure gold. There is a third symbol, which appears in the New Testament as well as the Old, and it is the most sacred of all. It is blood. Water, fire, blood--these three mean the same in Scripture. In this case it was fire. The seraph flew with the hot stone and laid it on the lips of the future prophet. Why did he lay it there? Because it was there that Isaiah felt his sin to be lying. He had said, "I am a man of unclean lips." The fire burned the sin away. So the seraph said, speaking in God's name, "Lo, this hath touched thy lips, and thine iniquity is taken away and thy sin purged." It was the assurance of the Divine forgiveness, which had come swift as a seraph's flight in answer to Isaiah's confession.[10] Isaiah's preparation was completed in these three successive phases of experience; and now the purpose was disclosed for which he had been prepared. From aloft--from the throne high and lifted up--came the question, "Whom shall I send, and who will go for us?" The King needed a messenger to bear a message and represent Himself. He had chosen Isaiah to bear it; yet He did not thrust the commission on him.[11] He did not need to do so; for Isaiah had passed through a preparation which made him not only thoroughly able, but thoroughly willing. He had been lifted out of time into eternity; and in this one hour of concentrated experience he had both died and been born again. His life had been undone and forfeited; but God had given it back to him, and he felt that now it was not his own. He was thrilling with the power of forgiveness, and the impulses towards God--to be near Him, to serve Him, to do anything for Him--were now far stronger than his shrinking from Him had been a little before. Therefore of his own free will and choice he answered the Divine question with, "Here am I, send me." * * * * *