Proverbs 27:17-19

Complete Jewish Bible

¹⁷ Just as iron sharpens iron,
    a person sharpens the character of his friend.

¹⁸ Whoever tends the fig tree will eat its fruit,
    and he who is attentive to his master will be honored.

¹⁹ Just as water reflects the face,
    so one human heart reflects another.