Flavius Josephus, Antiquities of the Jews
William Whiston, A.M., Ed.

[309] On the next day, Moses called the people together, with the women and children, to a congregation, so as the very slaves were present also, that they might engage themselves to the observation of these laws by oath; and that, duly considering the meaning of God in them, they might not, either for favor of their kindred, or out of fear of any one, or indeed for any motive whatsoever, think any thing ought to be preferred to these laws, and so might transgress them. That in case any one of their own blood, or any city, should attempt to confound or dissolve their constitution of government, they should take vengeance upon them, both all in general, and each person in particular; and when they had conquered them, should overturn their city to the very foundations, and, if possible, should not leave the least footsteps of such madness: but that if they were not able to take such vengeance, they should still demonstrate that what was done was contrary to their wills. So the multitude bound themselves by oath so to do.