With their staves — Probably as Moses smote the rock with his rod, so they struck the earth with their staves, as a sign that God would cause the water to flow out of the earth where they smote it, as he did before out of the rock. Perhaps they made holes with their staves in the sandy ground, and God caused the water immediately to spring up.
Related Commentaries of Numbers 21:18
Numbers 21:18
18 The princes digged the well, the nobles of the people digged it, by the direction of the lawgiver, with their staves. And from the wilderness they went to Mattanah: