impeccabilis

εἰρήνη ἡ ὑπερέχουσα πάντα νοῦν → peace that surpasses all understanding

Latin > English (Lewis & Short)

impeccābĭlis: (inp-), e, adj. 2. inpecco,
I faultless, sinless, impeccable, Gell. 17, 19, 6.