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

[163] Now when this report was spread abroad as far as the nations that bordered on Judea, that Gedaliah kindly entertained those that came to him, after they had fled away, upon this [only] condition, that they should pay tribute to the king of Babylon, they also came readily to Gedaliah, and inhabited the country. And when Johanan, and the rulers that were with him, observed the country, and the humanity of Gedaliah, they were exceedingly in love with him, and told him that Baalis, the king of the Ammonites, had sent Ishmael to kill him by treachery, and secretly, that he might have the dominion over the Israelites, as being of the royal family; and they said that he might deliver himself from this treacherous design, if he would give them leave to slay Ishmael, and nobody should know it, for they told him they were afraid that, when he was killed by the other, the entire ruin of the remaining strength of the Israelites would ensue. But he professed that he did not believe what they said, when they told him of such a treacherous design, in a man that had been well treated by him; because it was not probable that one who, under such a want of all things, had failed of nothing that was necessary for him, should be found so wicked and ungrateful towards his benefactor, that when it would be an instance of wickedness in him not to save him, had he been treacherously assaulted by others, to endeavor, and that earnestly, to kill him with his own hands: that, however, if he ought to suppose this information to be true, it was better for himself to be slain by the other, than to destroy a man who fled to him for refuge, and intrusted his own safety to him, and committed himself to his disposal.