Being a judge demands that one be above suspicion. Moreover, as the Sages illustrate in the following incident, judges must be meticulous in fulfilling the rulings that they themselves issue and instruct others to fulfill.

Judges must be vigorous in the performance of good deeds, as that is what Moses looked for in selecting them: “Moses selected capable men” (Exodus 18:25); men who were capable in Torah, good deeds, and courage.

Judges must be untainted by any suspicion of guilt, such that no person will have any contention against them; like Moses, who said to Israel: “Not one donkey did I take from them, nor did I wrong one of them” (Numbers 16:15), and like Samuel, who said: “Whose ox did I take, whose donkey did I take?” (I Samuel 12:3)….

There was an incident involving Rabbi Hanina ben Elazar, who had a tree planted in his field and its branches extended over the field of another. In addition, someone came and complained before him, and said: The tree of a certain person is extending into my field. Rabbi Hanina said to him: Go away and come back tomorrow. The man said to him: In all the cases that come before you, you issue a ruling immediately, and you delay my case? What did Rabbi Hanina do? Immediately, he sent his workers and had them chop down the tree that was in his field and extending over the field of another.

The next day, that man came before him for a ruling. Rabbi Hanina said to the other litigant: You must cut down the branches. He said to him: And why are the branches of your tree extending over the field of another? Rabbi Hanina said: Go out and look at it. Just as you see mine, so, do to yours. He went and did so. (Tanĥuma, Shofetim)