The Sages teach (Pirkei Avot 1,6): "Judge every person favorably" [though the literal translation is: "Judge the entire person favorably"]. This means that we must judge everyone favorably – both those who are good and those who are less good. 

This is considered a praiseworthy approach – as opposed to having criticism on everyone, which is a foul trait. But even worse than that is one who judges the evil ones favorably, while judging the good people negatively. King Shlomo in Proverbs (17,15) states this clearly: "To acquit the guilty and convict the innocent - both are an abomination to G-d." 

The renowned 18th-century Rav Yechezkel Landau, also known as the Noda B'Yehuda, explained this verse as follows: One who judges a wicked person favorably – that is not terrible; on the contrary, he has a good trait of finding the positive. And one who indicts, in his mind, the righteous – this is also not abominable, though it is not good. But one who does both of these – judging the wicked favorably and also the righteous negatively as he constantly seeks out their shortcomings – about him the verse states: "Both are an abomination to G-d."

The Gemara in Tr. Sanhedrin (p. 26a) tells us that R. Chiya bar Zarnoki and R. Shimon ben Yehotzadak were on the road to Asya to intercalate the year; they were unable to do so in Eretz Yisrael. Resh Lakish met them and decided to join up with them, for he wished to see how it was done. Along their way, Resh Lakish saw a man plowing a field. He said to the other Sages: "Look at this priest who is plowing during the Sabbatical Year [when working the land is forbidden]." They said to him that the man might be a hired worker in a Gentile-owned field, in which case it is permitted. 

Resh Lakish then saw another man pruning vines. He again said, "Look at this priest pruning vines during the Shemitah." They answered that he might need the branches to make a bale [ekel] for his olive press, i.e., not for agricultural purposes, in which case it is permitted. Resh Lakish said to them, in a play on words: "The heart knows whether he is doing so for a bale [ekel], as you say, or in deception [l’akalkalot]…"

The Gemara asks why Resh Lakish assumed the men were priests, and answers: "It is because priests are suspected of desecrating the Sabbatical Year…"

After Resh Lakish continually bothered them with his comments, the two Sages said that he was a nuisance. When they reached their destination where they intended to intercalate the year, they went up to the roof – and then removed the ladder so that Resh Lakish would not be able to join them. Some time later, Resh Lakish came to R. Yochanan and asked, "Are people who are suspected of desecrating the Sabbatical Year [that is, treating it with disrespect] fit to intercalate the year?!"

The question may here be asked: Why did Resh Lakish awaken to this problem only after they removed the ladder and didn't let him into the room? He could have raised this objection as soon as he saw them judging the two men favorably! 

The answer is in keeping with what we said above. At first, Resh Lakish thought that they were judging everyone favorably, which is of course a good trait. But when he saw that they didn't judge him favorably, but rather called him a nuisance and didn't let him join them in the intercalcation procedure, he thought to himself: "They judged them favorably, but not me. This means that they judge people favorably only when it is convenient for them. If so, then given that they judged only these Sabbatical-violators favorably, it could mean that they themselves are guilty of violating the Sabbatical laws." This can be what the Noda B'Yehuda was explaining. 

And thus, we must be careful not to behave in a distorted manner, but rather to judge everyone favorably – both those who are seemingly guilty and, all the more so, those who are righteous.

Translated by Hillel Fendel.