Midrash sur Osée 6:9

When Jacob’s sons learned what had transpired: The men were grieved, and they were very wroth, because he had wrought a vile deed in Israel in lying with Jacob’s daughter (ibid., v. 7). And they said unto them: “We cannot do this thing, to give our sister to one that is uncircumcised (ibid. v. 14), Go! Circumcise yourselves. They departed and circumcised themselves, as is said: And unto Hamor … harkened all (ibid., v. 24). And it came to pass on the third day, when they were in pain (ibid., v. 25). The prophet cried out: And as troops of robbers wait for man, so doth the company of priests; they murder in the way toward Shechem, yea, they commit enormity (Hos. 6:9). As troops of robbers wait for man (ish) refers to Jacob, who was a righteous man (ish tam), and he was forced to await the return of his sons from their pillaging.