The substance of God’s oath is that the many houses which have been expropriated will become desolate and deserted (without inhabitant); cf. 6:11, ‘Until
cities are left without inhabitant,
and houses without people, and the
land is utterly desolate’. This looks
very much like some form of catastrophe taking place in the land, and on the
face of things it is difficult to harmonize with the previous verse (note that inhabitant comes from the same verb as
‘dwell’, so that the two statements are saying exactly the opposite). (H. G. M. Williamson, A Critical and
Exegetical Commentary on Isaiah 1-27, 3 vols. [International Critical
Commentary; London: T&T Clark, 2006], 1:354)
On Isa 6:11
The description of the judgment as given in God’s reply (which,
incidentally, is also chiastically phrased) is relatively straightforward: the
built environment of cities and houses will be destroyed and emptied of
inhabitants while the land generally will be left as a wasteland. Cities, land, and wasteland all appear in 1:7 (q.v.)
as part of the description of (in my opinion) the Assyrian invasion of 701 bce,
but of course such a description need not be limited to that. At 5:9, for
instance, in addition to ‘houses’ and ‘desolate’ (שמה
beside שממה here) we also have the expression without a single inhabitant. (H.
G. M. Williamson, A Critical and Exegetical Commentary on Isaiah 1-27, 3 vols.
[International Critical Commentary; London: T&T Clark, 2018], 2:83-84)