To take root; to be firmly settled in their possessions, and not tossed hither and thither, as they have been. Fill the face of the world with fruit; their posterity shall be so numerous, that their own land shall not be sufficient for them, but they shall be forced to seek habitations in other countries, and shall replenish them with people. But this seems to be understood of the spiritual seed of Jacob, or of believers, who are oft called God's Israel, as Romans 9:6, and elsewhere.
Related Commentaries of Isaiah 27:6
Isaiah 27:6
6 He shall cause them that come of Jacob to take root: Israel shall blossom and bud, and fill the face of the world with fruit.