Moses is told to speak to the rock so it will give out water for the people. He hits the rock instead; water gushes forth, the people drink. And the perplexing consequence is the above verse; God tells Moses and Aaron that because of this, they will not enter the land of Israel. We learn from subsequent Torah passages that Moses desperately begs God to let him into the land, to no avail.

Many commentators struggle with the extremity of such a draconian punishment.

Rashi will say Moses's sin was that of disobedience - he hit the rock rather than speaking to it, as God instructed. Rambam will cite Moses's anger as the problem and Ramban pounces on the "slip" of Moses saying to Aaron "shall we take water from this rock" rather than "shall God".

All these explanations imply that Moses sins and is punished. Puzzlingly, in an earlier passage from the book of Exodus, there is a similar situation of the people needing water. Moses strikes a rock - water comes out - and there is celebration. So why is it so unacceptable to God this time around?

Rabbi Lord Sacks offers a different angle to the story, namely that Moses didn't sin and he wasn't punished. It is just that Moses was no longer the right leader for the Children of Israel. He did not appreciate that although hitting a rock worked then, a new approach was needed now. He was supposed to talk to the rock but instead he relied on the old technique that had been successful before.

Each new generation must search for their own leaders. Perhaps a parallel could be made with Winston Churchill, the great leader whose wartime success also did not translate into peacetime statesmanship. To Churchill's devastation, the very qualities that had made him a great leader in wartime were not suited to domestic peacetime politics.

Moses, too, had his victories and glories in the most dramatic moments of history, but his dream of being a peacetime leader in a new land was to be denied.