War on Shabbat
Gil at Hirhurim has a post discussing the description from the First Book of Maccabees 2:31-41 of how at first some of the rebels would not fight back on Shabbat, and it was only after they were slaughtered that the decision was made to fight on Shabbat. “So they made this decision that day: “Let us fight against every man who comes to attack us on the sabbath day; let us not all die as our brethren died in their hiding places.” (I Macc. 2:41) The prohibition against fighting on Shabbat is also known from the Book of Jubilees 50:12-13. As Prof. M.D. Herr has pointed out, from the text in First Maccabees we can see that the later rabbinic concept of pikuah nefesh was unknown to them at that time. When waging battle was finally permitted on Shabbat, it was more in the context of the permission to wage war on Shabbat and not necessarily related to a general principle that saving life takes precedence over the observance of Shabbat. What was the Shabbat prohibition that they would have violated if they would have fought back? It could have been that they did not want to leave their hiding places, not wanting to leave their dwelling place on the Sabbath. Another possibility is that they did not want to take a human life on the Sabbath (see Jubilees). A third possibility is offered by Y.D. Gilat who sees the episode in First Maccabees as reflecting a period when people were very strict regarding the prohibition of muktzeh (Gilat, pp. 95-96).
Sources:
Y.D. Gilat, Yad Le-Gilat; Jonathan Goldstein, The First Book of Maccabees in the Anchor Bible Series; M.D. Herr, “Le-Baayat Hilchot Milchamah Be-Shabbat…”, Tarbitz 30.