What does Genesis 28:14 mean?

'Your descendants will be as countless as the dust of the earth. You'll spread out in every direction—west, east, north, and south. Through you and your family, every family on earth will be blessed.' Genesis 28:14 - Modern Text Bible

(God repeats the promise made to Abraham: Jacob's family will become huge and will bring blessing to everyone on earth. It's a huge, world-changing promise.)