This article adresses the expression ydwë ḥly, which occurs in Isa 53,3 (МТ). The interpretation of this expression is a matter of some difficulty: the form of the word ydwë is based on the model of the passive participle, while the context indicates an active meaning. The author finds in Qumran texts evidence of the passive participle of the verb ydë “to know” with an active meaning. Thus, the author proves that the translation of ydwë ḥly as “who knows illness” is accurate. In addition, he proposes a hypothesis that explains the correlation between the Masoretic text and other versions. According to this hypothesis, the primary variant of the Hebrew text of this passage may be found in the Qumran Scroll 1QIsab, and the variants present in MT and 1QIsaa reflect later vocalization of the text.