Theodoret of Cyrus

It ought not to excite astonishment that Constantine was so far deceived as to send so many great men into exile: for he believed the assertions of bishops of high fame and reputation, who skillfully concealed their malice. Those who are acquainted with the Sacred Scriptures know that the holy David, although he was a prophet, was deceived; and that too not by a priest, but by one who was a menial, a slave and a rascal. I mean Ziba, who deluded the king by lies against Mephibosheth, and thus obtained his land. It is not to condemn the prophet that I speak in this way; but that I may defend the emperor, by showing the weakness of human nature, and to teach that credit should not be given only to those who advance accusations, even though they may appear worthy of credit; but that the other party ought also to be heard, and that one ear should be left open to the accused.