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

[66] BUT now the affairs in Herod's family were in more and more disorder, and became more severe upon him, by the hatred of Salome to the young men [Alexander and Aristobulus], which descended as it were by inheritance [from their mother Mariamne]; and as she had fully succeeded against their mother, so she proceeded to that degree of madness and insolence, as to endeavor that none of her posterity might be left alive, who might have it in their power to revenge her death. The young men had also somewhat of a bold and uneasy disposition towards their father occasioned by the remembrance of what their mother had unjustly suffered, and by their own affectation of dominion. The old grudge was also renewed; and they east reproaches on Salome and Pheroras, who requited the young men with malicious designs, and actually laid treacherous snares for them. Now as for this hatred, it was equal on both sides, but the manner of exerting that hatred was different; for as for the young men, they were rash, reproaching and affronting the others openly, and were inexperienced enough to think it the most generous to declare their minds in that undaunted manner; but the others did not take that method, but made use of calumnies after a subtle and a spiteful manner, still provoking the young men, and imagining that their boldness might in time turn to the offering violence to their father; for inasmuch as they were not ashamed of the pretended crimes of their mother, nor thought she suffered justly, these supposed that might at length exceed all bounds, and induce them to think they ought to be avenged on their father, though it were by despatching him with their own hands. At length it came to this, that the whole city was full of their discourses, and, as is usual in such contests, the unskilfulness of the young men was pitied; but the contrivance of Salome was too hard for them, and what imputations she laid upon them came to be believed, by means of their own conduct; for they who were so deeply affected with the death of their mother, that while they said both she and themselves were in a miserable case, they vehemently complained of her pitiable end, which indeed was truly such, and said that they were themselves in a pitiable case also, because they were forced to live with those that had been her murderers, and to be partakers with them.