See Matthew 23:23.
Rue - This is a small garden plant, and is used as a medicine. It has a rosy flower, a bitter, penetrating taste, and a strong smell.
Related Commentaries of Luke 11:42
Luke 11:42
42 But woe unto you, Pharisees! for ye tithe mint and rue and all manner of herbs, and pass over judgment and the love of God: these ought ye to have done, and not to leave the other undone.