John Gill Bible Commentary

And the Lord said unto Moses,.... Out of the pillar of cloud: go on before the people, lead them on nearer to Mount Sinai or Horeb, within sight of which they now were. Jarchi adds, by way of explanation, "and see if they will stone thee"; fear not, go on boldly, no harm shall come to thee: and take with thee of the elders of Israel; some of them for a witness, as the above writer observes, that they may see that by thine hand water comes out of the rock, and may not say there were fountains there from the days of old. These were taken, because they were the principal men among the people, who, as they were men of years, so of prudence and probity, and whose veracity might be depended upon; and since so great a multitude could not all of them see the miracle, the rock being smote, and the water only flowing in one part of it, and perhaps the road to it but narrow, it was proper some persons should be singled out as witnesses of it, and who so proper as the elders of the people? and thy rod, wherewith thou smotest the river, take in thine hand and go; wherewith the river Nile was smitten, and the water became blood, when Moses and Aaron first went to Pharaoh; and which, though smitten by Aaron, yet being with the rod of Moses, and by his order, is attributed to him; or else with which the Red sea was smitten by Moses, and divided; which being but a narrow channel, or an arm of the sea, might be called a river: and this circumstance is observed, as the afore mentioned writer thinks, to let the Israelites know, that the rod was not, as they thought, only designed for inflicting punishment, as on Pharaoh and the Egyptians, but also for bringing good unto them; and when they saw this in his hand, by which so many miracles had been wrought, they might be encouraged to hope that something was going to be done in their favour, and that water would be produced for them to drink.