The 144,000 in Revelation are similar to the "Sons of Light" in the War Scroll in another way. The way they are enumerated in 7:4-8 is suggestive of an army of soldiers because this passage has the literary form of a census. The purpose of a census in the OT was always to determine the number of people who can be conscripted into battle (cf. Numbers 1:20-46, 2:3-32, 26:2-51; 2 Samuel 24:1-9; 1 Chronicles 27:1-24). The repetition of ek phulés "from the tribe of" in Revelation 7:4-8 recalls the ek tés phulés "from the tribe of" in Numbers 1:21, 23, etc. (LXX). Such censuses also often draw equal numbers from each tribe, like the 12,000 chosen from each tribe in Revelation. In Numbers 31:4-6, 1,000 troops were dispatched from each tribe against Midian; the size of a battalion was 1,000 troops. Interestingly, the 144,000 in Revelation is composed of (12 x 12) x 1,000, such that the total of 12,000 soldiers from Israel sent against Midian in Numbers is what each tribe would furnish in the much greater war in Revelation (i.e. 12,000 troops x 12 tribes = 144,000). The War Scroll gives another parallel. In 1QM 6:11, an array of 6,000 horsemen is mentioned, 500 drawn from each tribe (i.e. 500 x 12 tribes = 6,000 in the cavalry). Moreover, the War Scroll organizes the army of the "Sons of Light" into contingents from the twelve tribes (cf. 1QM 2:2-3, 7, 3:13-14, 5:1-2, 6:10, 14:16). Furthermore, the individuals enumerated in the OT were males of military age, and Israelite soldiers were required to keep themselves chaste (Deuteronomy 23:9-10; 1 Samuel 21:5; 2 Samuel 11:8-11), and thus the 144,000 in Revelation 14:1-4 are "male virgins" undefiled by women. Similarly, the holy warriors of the War Scroll are all "volunteers for battle, pure of spirit and flesh", under the age of 30, and "any man who is not ritually clean in respect to his genitals on the day of battle shall not join them in battle" (1QM 7:3-6). At the same time, there is another striking similarity with the OT and apocalyptic war tradition in the "Great Crowd" who "wash their robes white in the blood of the Lamb" (Revelation 7:14). According to Numbers 31:19-24, the washing of garments was required after the shedding of blood as a form of ritual purification, and the War Scroll notes that the soldiers "shall wash themselves of the blood of the guilty cadavers" (1QM 14:2-3).
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