Cain had built his city on the human sacrifice of his brother (Gen. 4), and Nimrod built his city (culture) and Tower (worship center) of bricks. When we remember that man is made of dust (Gen. 2:7), and that God’s House is made of people, “living stones” (1 Pet. 2:4-8), we can see a double meaning in what we read here in Genesis 11. Nimrod’s world of bricks cemented by asphalt served to symbolize his unified society of men, all stuck together in one place, not spreading out and shepherding the world.
