And Moses and Aaron gathered the assembly together before the rock; and he said to them, “Hear now, you rebels! Must we bring water for you out of this rock?” Then Moses lifted his hand and struck the rock twice with his rod; and water came out abundantly, and the congregation and their animals drank. Numbers 20:10-11

Everyone makes mistakes.
Some mistakes are reversible and others are not.
Moses did the latter.
God’s instructed him, “Speak to the rock before their eyes, and it will yield its water.” Numbers 20:8

The list of mistakes grows in this scene.
First, he speaks to the people – Hear now, you rebels.
Second, he speaks about Aaron and himself – Must we bring water.
Third, he does not speak to the rock – Moses lifted his hand and struck the rock twice.

Much of what you do today does not involve an action other than speaking. You have the ability to change a life with a word of encouragement, a spoken prayer, or a just a blessing.

Moses discovered that disobedience to God often cascades in complications that lead to irreparable problems.
To put it plainly – Do not be deceived, God is not mocked; for whatever a man sows, that he will also reap. Gal 6:7