The waters of Meribah

Numbers 20:1-13
Now there was no water for the community, and the people gathered in opposition to Moses and Aaron. They quarreled with Moses.
The Lord said to Moses, "...speak to that rock before their eyes and it will pour out its water. You will bring water out of the rock for the community so they and their livestock can drink."
So Moses took the staff from the Lord's presence, just as he commanded him. He and Aaron gathered the assembly together in front of the rock and Moses said to them, 'Listen, you rebels, must we bring you water out of this rock?" Then Moses raised his arm and struck the rock twice with his staff. Water gushed out, and the community and their livestock drank.
But the Lord said to Moses and Aaron,"Because you did not trust in me enough to honor me as holy in the sight of the Israelites, you will not bring this community into the land I give them. These were the waters of Meribah.
The best part of 38 years has passed since 13:1. At Kadesh, on the borders of Edom, Miriam dies. Miriam, Aaron and Moses will all die in the same year - on the brink of entry into Canaan. Nothing seems to cure the people's grumbles. They were moaning when they first left Egypt. They are moaning still after all the years of god's providing.
The incident in verses 2-13 recalls the similar one at Mt Sinai. Moses' sin seems to lie in the words 'Must we get water...?', as if he and Aaron, not God, brought the water from the rock. How often words spoken in haste are repented at leisure. Because of this, Moses will not lead the people into the land he so longs to enter. Even the greatest of God's servants, after a long lifetime of trust and obedience, can fall.
Why?
Grumbles and quarreled with Moses seems never cease in Israelite community. Even Moses and Aaron were angry with these people and their mission. So Moses did not fully follow the word of God but struck the rock twice instead of once. Moses said the word with complain so God's angry came.
Moses is God's best servant, but he won't be able enter the promised land with community.
Fully follow with the Lord is different with follow part of God's command.
Worship the Lord with all my mind, all my heart and all my strength. This is what the Lord asked us.
How?
God always is right and with love to us, trust in the Lord for He is my God, I am his servant.