Jesus said to his disciples:

‘There is no sound tree that produces rotten fruit, nor again a rotten tree that produces sound fruit. For every tree can be told by its own fruit: people do not pick figs from thorns, nor gather grapes from brambles. A good man draws what is good from the store of goodness in his heart; a bad man draws what is bad from the store of badness. For a man’s words flow out of what fills his heart.’