The Messenger of Allah ﷺ said, "The believer is guileless and noble, while the corrupt person is deceitful and base."
قال رسول الله ﷺ: المؤمن غر كريم، والفاجر خب لئيم.
Narrated by Abu Yaala (6008), Tahawi in Sharh Mushkil (3128, 3129), and Hakim (1/43), all through chains going back to Sufyan Thawri, from Hajjaj bin Farafisa, from Yahya bin Abu Kathir, from Abu Salama, from Abu Hurairah, who related it. Its chain is hasan because of Hajjaj bin Farafisa, for he is hasan al-hadith, and it has been corroborated.It was narrated by Tirmidhi (1964), Abu Dawud (4790), and Bukhari in Adab al-Mufrad (418), all through the route of Bishr bin Rafi, from Yahya bin Abu Kathir, from Abu Salama, from Abu Hurairah, relating the same. However, Bishr bin Rafi Harithi is daif al-hadith, but he is corroborated in the first chain.As for what was narrated by Abu Dawud (4790) and Ahmad (9118), both through the route of Abu Ahmad (that is, Zubayri), who said, Sufyan Thawri narrated to us, from Hajjaj bin Farafisa, from a man, from Abu Salama, from Abu Hurairah, with the same wording, it contains an unnamed man, who is Yahya bin Abu Kathir, as mentioned above.The meaning of the hadith. Khattabi said, "The meaning of this statement is that the praiseworthy believer is one whose nature and character are marked by guilelessness, a lack of shrewdness toward evil, and a disinclination to probe into it, and this is not out of ignorance on his part but rather generosity and good character. The wicked person, on the other hand, is one whose habit is deceit, cunning, and delving deeply into the knowledge of evil, and this is not intelligence on his part but rather deceit and baseness." Maalim Sunan (4/108).