ἐπιορκέω
οὐ γὰρ ἂν τό γε πραχθὲν ἀγένητον θείη → since he cannot make what was done as though it had not come to pass
English (LSJ)
also ἐφιορκέω IG22.1126.9 (Delph. Amphict.), OGI 229.69 (Smyrna, iii B.C.), etc.: fut.
A -ήσω Il.19.188, Ar.Lys.914, etc., -ήσομαι (κατ-) D.54.40: aor. ἐπιώρκησα Id.49.67, inf. -ορκῆσαι Hdt. 4.68 (v.l. ἐφ-): pf. ἐπιώρκηκα Pl.Lg.948e, X.An.3.1.22, Din.1.47 (ἐπιόρκηκα is v.l. in Hdt.l.c.):—swear falsely, forswear oneself, οὐδ' ἐπιορκήσω πρὸς δαίμονος Il.19.188: also, c.acc., of things sworn by, τὰς βασιληΐας ἱστίας ἐπιώρκηκε has sworn falsely by the royal hearth, Hdt.4.68; θεάς Din.1.47; [θεούς] Ar.Av.1609, X.An.2.4.7, D.49.67, etc.: mostly abs., Ar.Eq.298,428, Nu.402, Pl.Phlb.65c, etc.; οὐδὲν ἐφρόντιζ' ἐπιορκῶν D.21.119: c.acc.cogn., ἐ. ὅρκους τινί Id.49.65, cf.Aeschin.1.115; opp. εὐορκέω, Lexap.And.1.98, Cleanth.Stoic.1.131, Chrysipp.ib.2.63, who distinguishes betw. εὐορκεῖν and ἀληθορκεῖν, and betw. ἐπιορκεῖν and ψευδορκεῖν. II. simply, = ὄμνυμι, swear, Sol. ap. Lys.10.17.