C. F. Keil and Franz Delitzsch on Isaiah 27:6

Isa 27:6

The prophet now adds to the song of the vineyard, by way of explanation. “In future will Jacob strike roots, Israel blossom and bud, and fill the surface of the globe with fruits.” We may see from הבּאים (acc. temp. as in Ecc 2:16, equivalent in meaning to “Behold, the days come,” Jer 7:32, etc.), that the true language of prophecy commences again here. For the active וּמלאוּ, compare Jer 19:4; Eze 8:17, etc. The prophet here says, in a figure, just the same as the apostle in Rom 11:12, viz., that Israel, when restored once more to favour as a nation, will become “the riches of the Gentiles.”