PWS

*rpy - to relax (Kogan 2015: 121)

*rpˀ ‘to heal, to protect’ is probably connected perhaps also Arb. rfh - ‘to be easy, soft, delicate’ and Soq. bə-rέfɛy/bə-rέfɛš - ‘slowly, gently’

Hebrew
rpy - to grow slack (HALOT 1276)
Syriac
rpy - to be lax, slack (LSyr. 740, SL 1483)