The prophet Isaiah (this is "First" Isaiah, a contemporary of Micah) knows of the Assyrian conquest of the northern kingdom, Israel, and the Assyrians are besieging Judah and Jerusalem. God is working in this, and he begins chapter 2 articulating a vision that seeks to describe God's promise for his people. The question is whether the people will follow God's invitation into the light, or opt for the comforts of the familiar amid the darkness.
Jesus has a similar task. He depicts another occasion of God's "creative destruction," at the coming of the Son of Man at the end of the age. (It seems an odd place to start the Advent-Christmas season, but the start of Advent typically makes reference to the cataclysmic events of the second coming, even as we're considering the first coming in our liturgical calendar.)
Jesus contrasts average, everyday people at their normal tasks. One gets taken up while the other remains. Why is that? The answer awaits in the sermon video below, plus the downloads below the video panel.