וְהִנֵּ֨ה עָ֘לָ֤ה כֻלּ֨וֹ ׀ קִמְּשֹׂנִ֗ים כָּסּ֣וּ פָנָ֣יו חֲרֻלִּ֑ים וְגֶ֖דֶר אֲבָנָ֣יו נֶהֱרָֽסָה׃
И вот, все это было покрыто чертополохом, лицо его было покрыто крапивой, и его каменная стена была разрушена.
Rashi
nettles חרלים. They are larger than thistles, and they are as sharp as thorns.
Rashi
and its stone fence had been torn down Thus, one who does not review his studies first forgets the beginnings of the chapters and at the end confuses the names of the Sages from this one to that one, thereby saying “unclean” for something that is clean and “clean” for something that is unclean, and he destroys the world.