After his depressing assessment of the civil and religious leaders, recorded in Micah 3, it must have been very refreshing for Micah now to have the privilege of describing the rule of the righteous ruler, the Messiah.
Micah describes the kingdom of God as it will be in the latter days (the days of the Messiah). During that time, the location of the worship of God will be elevated higher than all other prominent places. We know that it cannot get any higher because it takes place in God's presence in heaven, where Jesus rules now, having received universal dominion as the reward for his sufferings on the cross.
Those participating in the worship of God will come from many different countries. It will be a people movement that cannot be surpassed anywhere or at any time. Their participation will be like a flowing river that keeps on deepening and widening. That is what is happening today in the kingdom of Jesus as more and more people join it and discover its riches.
Why will they take part in the worship of God? They will do so because they want to be instructed in the ways of God. It may be that the Lord is referred to as the God of Jacob because of the persevering grace that was shown to him as an individual. Jacob received grace repeatedly.
Divine instruction is never merely intellectual - it always involves practical elements as we walk in his paths. Those paths always involve dedication to the King and discussion with him as their routes are discovered and their details revealed.
The response of his followers is described in verse 5. No matter what others do, they want to serve God forever. The foretastes they enjoy now create a longing to have more. And they have discovered that their God is able to satisfy their longing souls.