Moses and the Israelites were camped at Rephidim and the people were thirsty again. They quarrelled with Moses, which means they verbally attacked him because it was HIS fault! This passage says that the people "tested" God here and so God named it "Test and Struggle" (in Hebrew, of course). Eventually, God told Moses to strike a rock and water poured out, enough for as many as two-million people! That rock was a symbol of Christ, who would be "struck" for us, and who would give us Living Water which saves us!