en_tn_condensed/mat/12/35.md

The good man from the good treasure of his heart produces what is good, and the evil man from the evil treasure of his heart produces what is evil

Jesus speaks about the “heart” as if it were a container that a person fills with good or evil things. This sentence means what a person says shows what the person is truly like. Alternate translation: “A good man will speak good things because good things are in his heart, and an evil man will speak evil things because evil things are in this heart”