36 But they did not answer them or hurl a stone at them or block up their hiding places, 37 for they said, "Let us all die in our innocence; heaven and earth testify for us that you are killing us unjustly." 38 So they attacked them on the sabbath, and they died, with their wives and children and livestock, to the number of a thousand persons. 39 When Mattathias and his friends learned of it, they mourned for them deeply. 40 And all said to their neighbors: "If we all do as our kindred have done and refuse to fight with the Gentiles for our lives and for our ordinances, they will quickly destroy us from the earth." 41 So they made this decision that day: "Let us fight against anyone who comes to attack us on the sabbath day; let us not all die as our kindred died in their hiding places."

The Sages taught in a Tosefta: One may not lay siege to cities of gentiles fewer than three days before Shabbat, to avoid the need to desecrate Shabbat in establishing the siege. And if they already began establishing the siege fewer than three days before Shabbat, they need not stop all war-related actions even on Shabbat. And so Shammai would say: From that which is written: “And you should build a siege against the city that is waging war with you until it falls” (Deuteronomy 20:20), it is derived that the siege should be sustained “until it falls.” Consequently, the siege must continue even on Shabbat.