Дварим 29:22 Комментарий: Ibn Ezra, Sforno, Rabbeinu Bahya & Chizkuni

brimstone… They will pray to God that all the land be scorched with brimstone and salt, as in the overthrow of the places mentioned. Some commentators say, however, that the subsequent verb “they will say” [: 23] does not introduce a new sentence, but that it is only a repetition of the previous verb “will say” [: 21]. The verb is repeated, following the rules of Hebrew usage, because of the length of the intervening clause. They i.e., the older generation will answer.

'גפרית ומלח....במהפכת סדום אשר הפך ה, the people seeing this know full well that this was not something accidental but that it is a finger of G’d. The comparison is based on Sodom seeing that its destruction had both been predicted to Avraham and confirmed by Lot and his daughters who were survivors of that event.

שרפה כל ארצה, “a burning up of its entire land;” according to the plain meaning of the text the word ארצה refers back to what the Torah described in verse 21 as “the plagues which afflicted that land.” In that verse the land had been described generally, whereas in our verse the Torah gives some details of what precisely happened to the land, i.e. that it was “burned” by sulphur and salt. The Torah now makes clear that this affliction struck the entire land.
Alternatively, the words כל ארצה, can mean that the choicest part of Israel’s land was turned into something similar to Sodom and Gomorrah which had been destroyed by sulphur and brimstone.