u/NkhukuWaMadzi

For he was both prone to evil doing and easily led astray -- both knave and fool, to use a common phrase: he never spoke the truth himself to those he happened to be with, but in everything that he said or did there was always a dishonest purpose; yet to anyone who wanted to deceive him he was easy meat. He was by nature an extraordinary mixture of folly and wickedness inseparably blended.

. . . [he] was dissembling, crafty, hypocritical, secretive by temperament, two-faced; . . .lying all the time; not carelessly, however, but confirming his undertakings both with his signature and with the most fearsome oaths, when dealing with his own subjects. But he promptly disregarded both agreements and solemn pledges

A treacherous friend and an inexorable enemy, he was passionately devoted to. . . plunder; quarrelsome and subversive in the extreme; easily led astray into evil ways but refusing any suggestions that he should follow the right path; quick to devise vile schemes and to carry them out; and with an an instinctive aversion to the mere mention of anything good.

Procopius' description of the Emperor Justinian