Isaiah's encounter with God in this week's haftarah is an evocative parallel of Moses's experiences in the corresponding Torah portion. Isaiah's reportage is fantastical: God sits upon a high and lofty throne, his robe filling the Temple with six-winged angels surrounding Him. Moses is similarly awed as went up to God (Exodus 19:3) to receive instructions before the giving of the 10 Commandments, the central motif of this week's portion.

Isaiah questions his ability to carry out God's message: "Woe is me, I am ruined because I am a man of unclean lips." What did Moses say when picked by God to be his messenger? "I am slow of speech and slow of tongue". Both Isaiah and Moses experience a tension between their human frailties and God's expectations of them. Both are saved by an angel and a piece of coal: Isaiah is struck by an angel, who comes to him with a hot coal taken from the Temple altar and presses the coal against his lips.

Cured of any speech defect, Isaiah has the strength to carry out God's instructions. According to a midrash , Moses is saved from death by a hot coal (Exodus Rabbah 1:26). Pharaoh's advisers were scared that Moses would grow up and usurp the king and a simple test was devised. A gold vessel and a hot coal were put in front of Moses - if Moses reached for the gold, he would die, but if he reached for the coal he would be saved. Just as he was about to touch the gold, the angel Gabriel came and forced his hand to touch the coal, thus saving his life.

Opportunities for transformative moments are often hidden: and like Isaiah and Moses, our challenge is to recognise the signs and find the words to acknowledge them.