Jamieson, Fausset and Brown on Isaiah 29:17

17. turned--as contrasted with your "turnings of things upside down" (Is 29:16), there shall be other and better turnings or revolutions; the outpouring of the Spirit in the latter days (Is 32:15); first on the Jews; which shall be followed by their national restoration (see on Is 29:2; Zec 12:10) then on the Gentiles (Joe 2:28).

fruitful field--literally, "a Carmel" (see on Is 10:18). The moral change in the Jewish nation shall be as great as if the wooded Lebanon were to become a fruitful field, and vice versa. Compare Mt 11:12, Greek: "the kingdom of heaven forces itself," as it were, on man's acceptance; instead of men having to seek Messiah, as they had John, in a desert, He presents Himself before them with loving invitations; thus men's hearts, once a moral desert, are reclaimed so as to bear fruits of righteousness: vice versa, the ungodly who seemed prosperous, both in the moral and literal sense, shall be exhibited in their real barrenness.