Testing the Rock

All the congregation of the people of Israel moved on from the wilderness of Sin by stages, according to the commandment of the LORD, and camped at Rephidim, but there was no water for the people to drink. Therefore the people quarreled with Moses and said, "Give us water to drink." And Moses said to them, "Why do you quarrel with me? Why do you test the LORD?" But the people thirsted there for water, and the people grumbled against Moses and said, "Why did you bring us up out of Egypt, to kill us and our children and our livestock with thirst?" - Exodus 17:1-3

Safe for Eternity

“The Bible often refers to God as a Rock. He is ‘the Rock of Israel’ (Gen. 49:24; cf. Isa. 30:29), ‘the Rock . . . [whose] works are perfect’ (Deut. 32:4), the Rock who is a ‘fortress’ and a ‘refuge’ (Ps. 18:2). He is ‘the Rock of our salvation’ (Ps. 95:1; cf. Deut. 32:15). In keeping with this imagery, the rock that Moses struck with his rod was a symbol of God and his salvation. In particular, it showed how God would submit to the blow of his own justice so that out of him would flow life for his people.

God did this in the person of his own Son. The rock was Christ because like the rock, Christ was struck with divine judgment. This is what happened to him on the cross. Christ was bearing the curse for our sin; so God struck him with the rod of his justice. The Scripture says, ‘He was pierced for our transgressions, he was crushed for our iniquities; the punishment that brought us peace was upon him, and by his wounds we are healed’ (Isa. 53:5). The judgment that Christ received on the cross is the proof of our protection. It shows that we will not suffer eternal death for our sins. God has taken the judgment of our guilt upon himself, and now we are safe for all eternity.” Exodus - Preaching the Word Commentary