“The ancient man approached God (or even the gods) as the accused person approaches his judge. For modern man the roles are reversed. He is the judge: God is in the dock. He is quiet a kindly judge: if God should have a reasonable defense for being the God who permits war, poverty, and disease, he is ready to listen to it. The trial may even end in God’s acquittal. But the important thing is that Man is on the Bench and God is in the Dock.” —C.S. Lewis
Three times Yahweh has tested Israel in the wilderness (Exodus 15:25–26; 16:4; Psalm 81:7). When you take a test three times, you hope to see some progress. Israel scores worse. Discontent to merely grumble, she quarrels and tests. God is testing her, and she tries to flip the tables. She tries to put God in the dock.
The word “test” has a legal flavor to it, a flavor that grows more pronounced as one advances through the text. God tells Moses to go ahead of the people with the elders. Why the elders?
“If a man has a stubborn and rebellious son who will not obey the voice of his father or the voice of his mother, and, though they discipline him, will not listen to them, then his father and his mother shall take hold of him and bring him out to the elders of his city at the gate of the place where he lives, and they shall say to the elders of his city, ‘This our son is stubborn and rebellious; he will not obey our voice; he is a glutton and a drunkard.’ Then all the men of the city shall stone him to death with stones. So you shall purge the evil from your midst, and all Israel shall hear, and fear (Deuteronomy 21:18–21 ESV).”
The elders function as judges and witnesses. A rebellious son is brought before the elders, seen guilty, and then judged. Israel tried to judge God and was on the cusp of sentencing. Of course she couldn’t kill God, so the mediator would have to do (Exodus 17:4). God takes His rebellious son out before the elders. He instructs Moses to bring the staff with which he struck the Nile. Every time this staff falls, it falls with salvation and judgment. Previously, Egypt was judged; Israel was saved. Here Israel is the guilty one. Israel is guilty, but she isn’t struck. The rock is struck so that she might drink. Paul tells us that this rock was Christ (1 Corinthians 10:4).
God is indeed in the dock, but He remains on the Judge’s bench as well. The Father still sat over the court judging our sins, but the Son willingly takes our place so that water might flow.