In Numbers chapter 20, the Israelites are in the wilderness of Zin and are in need of water. Moses is instructed by God to take his staff and speak to a rock in order to bring forth water. However, instead of speaking to the rock, Moses strikes it twice with his staff. This angers God and He tells Moses and Aaron that because of their disobedience, they will not be allowed to enter the Promised Land.
This chapter serves as a reminder to us that God is holy and just and that He expects us to obey Him. We must be careful to follow His instructions and not take matters into our own hands. We must also remember that disobedience has consequences, and that God will not overlook our sins. This chapter also serves as a reminder that God is merciful and forgiving, and that He will forgive us if we repent and turn away from our sins.