'Harmful' in the Bible

Someone went out to the field to gather some herbs and found a wild vine. He picked some of its fruit, enough to fill up the fold of his robe. He came back, cut it up, and threw the slices into the stew pot, not knowing they were harmful.

But he replied, "Bring me some flour." He tossed it into the pot and said, "Serve the people so they can eat." Then there was nothing harmful in the pot.