Answer: He said impetuous words, attributed God’s work to himself, and did not respect God as holy in front of others.
Deuteronomy 32:48 That same day the LORD commanded Moses, saying, Deuteronomy 32:49 Go up to Mount Nebo, which is among the mountains of Abarim, opposite Jericho in the land of Moab, and see what I will give to Israel. Canaan, the land of man. Deuteronomy 32:50 You shall die and be returned to your fathers on the mountain where you ascended, just as your brother Aaron died on Mount Hor and was returned to his fathers. Deuteronomy 32:51 Because you have sinned against me by not hallowing me holy among the children of Israel in the waters of Meribah at Kadesh in the wilderness of Zin. Deuteronomy 32:52 You may look at the land I am giving to the children of Israel from afar, but you may not enter it.