בַּיּ֨וֹם הַה֜וּא יִהְי֣וּ ׀ עָרֵ֣י מָעֻזּ֗וֹ כַּעֲזוּבַ֤ת הַחֹ֙רֶשׁ֙ וְהָ֣אָמִ֔יר אֲשֶׁ֣ר עָזְב֔וּ מִפְּנֵ֖י בְּנֵ֣י יִשְׂרָאֵ֑ל וְהָיְתָ֖ה שְׁמָמָֽה׃
In that day shall his strong cities be as the forsaken places, which were forsaken from before the children of Israel, after the manner of woods and lofty forests; and it shall be a desolation.
Read kabbalistic (mystical) interpretation of Isaiah 17:9: and classical mystical sources.