Proverbs 25:19-21

Complete Jewish Bible

¹⁹ Relying on an untrustworthy person in a time of trouble
    is like [relying on] a broken tooth or an unsteady leg.

²⁰ Like removing clothes on a chilly day or like vinegar on soda
    is someone who sings songs to a heavy heart.

²¹ If someone who hates you is hungry, give him food to eat;
    and if he is thirsty, give him water to drink.