"When Israel murmured against God and against Moses because they could get no water, they accused him of leading them out to kill them and their children. God heard their murmurings and bade Moses speak to the rock, that the people might have water. Moses smote the rock in wrath and took the glory to himself. The continual waywardness and murmuring of the children of Israel had caused him the keenest sorrow, and for a little time he forgot how much the Lord had borne with them, and that their murmuring was not against him, but against God. He thought only of himself, how deeply he was wronged, and how little gratitude they manifested in return for his deep love for them. EW 163.1"
"And Moses and Aaron gathered the congregation together before the rock, and he said unto them, Hear now, ye rebels; must we fetch you water out of this rock? And Moses lifted up his hand, and with his rod he smote the rock twice: and the water came out abundantly, and the congregation drank, and their beasts also. And the Lord spake unto Moses and Aaron, Because ye believed me not, to sanctify me in the eyes of the children of Israel, therefore ye shall not bring this congregation into the land which I have given them."
The EGW passage directly recounts the story of Moses striking the rock for water, as described in Numbers 20:10-12. It includes details such as the murmuring of the Israelites and Moses' taking the glory for himself, making it a clear and direct allusion.