Micah has just preached a message in which he pointed out the sins of his people. Yet he does not leave it there. Instead of leaving them to look inwardly at themselves he leads them to look away from themselves to a future time when there will be divine regathering of Israel. He reminded them of the Messiah who was to come.
In the exiles imposed on them by the empires of Assyria and Babylon, the Israelites had been scattered all over the world. When the exile in Babylon was over, most of the Israelites did not return to the land of their fathers. So the promised gathering was not fulfilled then. Good as the return was, it did not involve the Messiah's recovery of his people.
Micah described the work of the Messiah as that of a shepherd who would gather his people together. Then he will provide a place of safety for them (a fold) even although they will be surrounded by the threatening noises of others. No matter how loud the noise of their enemies they will be safe in the Shepherd's care.
Another image is used in verse 13. The people are besieged in a city with no way of escape. Suddenly a breach is made by their king and he leads them to safety. The deliverance is complete and they march in victory behind their leader, who turns out to be the Lord. Here is Micah pointing to the wonderful reality that the Messiah would be a divine person.
As a good preacher and a faithful servant, he drew the attention of his audience to Jesus. He is the one we should think about. After all, he will provide safety and victory for us. When he came, he defeated our enemies when he suffered on the Cross. Since then He is the Shepherd King who is gathering his people together from all over the world, who will look after his people in this life as they are surrounded by noisy opponents, and will lead them in triumph for ever as they share the fruits of his victory (Rev. 7:17).