Genesis 49:5

And it came to pass on the third day, when they were sore, that two of the sons of Jacob, Simeon and Levi, Dinah's brethren, took each man his sword, and came upon the city unawares, and slew all the males.

Of the children of Simeon, their generations, by their families, by their fathers houses, those that were numbered thereof, according to the number of the names, by their polls, every male from twenty years old and upward, all that were able to go forth to war;