Although it’s often repeated, no one knows where the phrase “the eyes are the windows of the soul” originated. The sentiment is carried through in the belief that looking (deeply) into someone’s eyes will tell you whether they love you, or can be trusted in a business deal, or are a “good person”.
Today’s readings (Sirach 27:4-7 and Luke 6:39-45) suggest a more obvious and, I would suggest, a more plausible foundation for understanding other people: listen to what they say. Maybe “the voice is the window to the soul”. If we want to know if someone is a good person, listen to what they say. If what they say consists of insults, threats, denunciations, disparagement, falsehoods, then they are revealing the evil inside them.
Jesus adds a severe warning to this simple approach. This warning is also based on an obvious truth – we are inclined to overestimate our strengths and underestimate our weaknesses when we compare ourselves with others. This is not universally true. Some people suffer the reverse problem – they always feel themselves inadequate in comparison with others.
The best answer to this challenge, whichever way round it afflicts us, is to stay out of the comparison business. But comparison or not, we do sometimes have to judge whether someone is a person we can or should follow. Listen to what they say. In Jesus’ words:
A good person out of the store of goodness in his heart produces good,
but an evil person out of a store of evil produces evil;
for from the fullness of the heart the mouth speaks.