What are some mistakes of Moses in the Bible?

Answer 1

God told Moses to take a rod, the one with which he struck the river and go and strike the rock and water will come out of it and the people will drink. So Moses (Exodus 17:7) went and struck the rock as he was told and water flowed from it.

Later, in Numbers 20:8-11, God told Moses to now go and "Speak to the rock before their eyes, and it will yield its water." But Moses, who was still angry with the people, struck the rock, thus disobeying the word of the Lord. Water flowed from the rock, but because of His disobedience, Moses was not permitted to enter into the land of Canaan (the promised land).

Answer:

Another instance was when Moses forgot that his brother's being a mourner prevented him from eating the sacrifice (Leviticus ch.9-10).

It should be pointed out that the claim to infallibility is a sure sign of forgery. We actually take pride in the fact that the Torah isn't like that: it unflinchingly publicizes the mistakes of its protagonists, since it wasn't a human invention.