For a good tree brings not forth corrupt fruit; neither does a corrupt tree bring forth good fruit.
All Commentaries on Luke 6:43 Go To Luke 6
Cyril of Alexandria
AD 444
See again, Christ commands that those who come to us must be distinguished not by their clothing but by what they really are. “By its fruit,” he says, “the tree is known.” It is ignorance and folly for us to expect to find the choicer kinds of fruits on thorns, grapes for instance, and figs. So it is ridiculous for us to imagine that we can find in hypocrites and the profane anything that is admirable, such as the nobleness of virtue….This is also made clear by another declaration of our Lord. “The good man,” he says, “as out of a good treasure, pours forth from the heart, good things.” One who is differently disposed, and whose mind is the prey of fraud and wickedness, necessarily brings forth what is concealed deep within. The things that are in the mind and heart boil over and are vomited forth by the stream of speech that flows out of it. The virtuous person therefore speaks such things as become his character, while one who is worthless and wicked vomits forth his secret impurity. Commentary on Luke, Homily
