When her people fell. Since this clause immediately follows the major metrical pause marking the middle of the verse in the Hebrew Bible (see p. 544), it properly belongs to the latter half of the verse rather than to the first half.
Sabbaths. Heb. mishbathim. This word occurs only here in the OT, hence its exact meaning is uncertain. The noun mishbath is derived from the verb shabath, “to cease,” “to rest,” from which the noun shabbath, “sabbath,” is also derived. Therefore many translators have considered mishbath as synonymous with the related word shabbath.
Jewish tradition also recognizes this interpretation (Midrash Rabbah, Lamentations, sec. 34). Recent translators have preferred to go closer to the root meaning of the verb shabath, and consider mishbath to mean “cessation,” etc. Mishbath is also closely related to the noun shebeth, “inaction [caused by sickness].” As there is evidence that before the fall of Jerusalem the Jews were not keeping the Sabbath (Jer. 17:19–27), it would seem that her enemies would hardly now mock at her for her Sabbaths unless at her belated attention to it. The reference is here perhaps more broadly to the mocking at the downfall (see RSV) and general desolation of Judah.