What is meant by Sufyan ibn Uyaynah's saying: "Whoever among our scholars is corrupt, then he resembles the Jews, and whoever among our worshippers is corrupt, then he resembles the Christians"?

The meaning of Sufyan ibn Uyaynah's saying is that corrupt scholars resemble the Jews who went astray despite their knowledge, and corrupt worshippers resemble the Christians who went astray due to their ignorance. As for "those on whom Allah has bestowed favor," they are those who knew the truth and acted upon it. This is why we supplicate in Al-Fatihah with: "Guide us to the straight path – the path of those upon whom You have bestowed favor, not of those who have evoked [Your] wrath or of those who are astray." Here, "those who have evoked [Your] wrath" are the Jews, and "those who are astray" are the Christians. The lesson lies in the generality of the wording, not in the specificity of the reason.