Our Gemara on Amud Aleph delves into the case of a slave with severe character flaws, such as being a thief or a "kubyostos". One might argue that the buyer is entitled to a refund, but the Gemara maintains that such character defects are common among slaves, making the purchase still valid.
The term "kubyostos" is defined by Rashi as a kidnapper, and by Tosafos as a gambler.
This derogatory term appears in two other Midrashim: one involving Yaakov and the angel he wrestled with, and another concerning accusations about Moshe. In the Gemara (Chulin 91a-b), the Angel is referred to as a "kubyostos," and it suggests that one sage claims the Angel appeared to Yaakov as a Gentile, while another claims he appeared as a Talmid Chacham. Similarly, Moshe is accused of being a "kubyostos" and libeled as not keeping honest calculations (Bechoros 5a).
The term "kubyostos" carries a spiritual meaning of ambiguity, representing both potential good and bad. He is a trickster; his external appearances can't determine whether someone is a friend or foe. (This is certainly true for the Gambler, but I think we can see how a kidnapper must be exceptionally crafty to lure his victim.) Shalah (Torah Shebikhtav, Vayishlach, Torah Ohr, 14) explains that the sages weren't actually debating the reality. Rather, each sage discussed a different potential that Yaakov saw in Esav. Esav, and his spiritual representation, had the capacity for both good and evil, along with dimensions of greatness. Yaakov himself was uncertain about his upcoming reunion with his brother. What path had Esav chosen over the years that they were apart?
Similarly, Toldos Yaskov Yosef (Lech Lecha 15) suggests that Moshe was accused of being a "kubyostos" because he also possessed two natures. According to him, Moshe had inclinations towards thievery and immorality but overcame these tendencies to pursue spiritual greatness.
This principle appears universally valid: the greater the potential for evil, the greater the potential for good, and vice versa. This should provide some comfort when confronting our darker impulses and behaviors. Every aspect of ourselves contributes to the whole.
Translations Courtesy of Sefaria, except when, sometimes, I disagree with the translation 
Do you like what you see? Please subscribe and also forward any articles you enjoy to your friends, (enemies too, why not?)