'Bitter' in the Bible

Beware that the heart of no man, woman, clan, or tribe among you turns away from the Lord our God today to pursue and serve the gods of those nations; beware that there is among you no root producing poisonous and bitter fruit.

For their vine is from the stock of Sodom, and from the fields of Gomorrah. Their grapes contain venom, their clusters of grapes are bitter.