Let him turn away (ekklinatō). First aorist active imperative third person singular of ekklinō, where the lxx has ekklinon (second person singular). Old verb, in N.T. only here, Rom 3:12; Rom 16:17. Peter adapted the passage all through to his own construction and use. So as to poiēsatō (let him do) for poiēson (do thou), zētēsatō (let him seek) for zētēson (do thou seek), diōxatō (let him pursue) for diōxon (do thou pursue), all first aorist active imperatives (of poieō, zēteō, diōkō). See Heb 12:14 for “pursuing peace.” If men only did!