Once on a time a great many people left their homes and started to move to a new country. They had to walk all the long way. The little boys and girls and even the old grandfathers and grandmothers had to walk, too.

Sometimes the road which they traveled led through pleasant places, where the ground was smooth and easy to walk upon. Sometimes it led across hills and through valleys, where the ground was rough; then they would feel very tired.

One day these travelers came to a desert place. Everywhere they looked they saw sand and rocks. And the sun shone down so warm upon their heads that soon they felt tired and thirsty. In a short time they had drunk every drop of the water which they had brought for the day's journey.

Then Moses, their brave leader, prayed to God. And God said, "Take your rod and go before these people to the rock in Horeb. I will be there; and when you strike the rock, water will flow out of it." Moses obeyed, and soon the people saw a stream of clear water flowing over the sand. They drank of it and were glad. -Exodus 17:1-8.