Both 1 Maccabees and 2 Maccabees portray the Sabbath law as a central point of con- tention during the struggle over Judean law and tradition in the second century BCE (e.g., 1 Macc 1:41-50; 2 Macc 6:4-6). The Hasmonean family in particular is at times high- lighted as holding the Sabbath in high regard (2 Macc 5:27). In every available source, there is no question of the commitment to the inherited traditions concerning the Sabbath. However, in two passages, 1 Macc 2:29-41 and 9:43-53, the Hasmoneans are portrayed as acting in a way supported by few extant writings associated with Judean legal tradition: they engage in battle on the Sabbath. First Maccabees presents this as innovation on the part of the Hasmoneans. Josephus, who summarizes these events based upon 1 Maccabees, even recognizes this decision as the basis for normative prac- tice (Ant. 12.272-277). As several scholars (e.g., Bar Kochva, Weiss, Scolnic) have pointed out, this event could hardly have been the first time in Judean history the issue arose. They argue against this reading of the sources. This paper contends that the plain read- ing of the texts is correct and 1 Maccabees is being used as the basis for legal practice in Josephus’ writings.