PRK42.6 :הוו זהירין למיגזי לטבא טיבותא‏ : be careful to repay goodness to the good one
See the entire entry for zhīr adj. cautious

PRK42.6 :הוו זהירין למיגזי לטבא טיבותא ולמיגזי לבישה בישתה‏ : be careful to repay the good person with goodness and to repay the evil one with his evil
See the entire entry for ṭaybū/ṭēḇū, ṭaybūṯā/ṭēḇūṯā n.f. kindness; Grace