ἐπιβεβαίωσις
From LSJ
ἡ ὑπόστασίς μου ὡσεὶ οὐθὲν ἐνώπιόν σου → my life is as nothing in respect to you, my life is nothing in thy reckoning
English (LSJ)
εως, ἡ,
A further confirmation, Id.Rh.Al.1438b29 (pl.); guarantee, Sammelb. 5240.17 (i A.D.).
Greek (Liddell-Scott)
ἐπιβεβαίωσις: -εως, ἡ, ὡς καὶ νῦν, περαιτέρω βεβαίωσις, Ἀριστ. Ρητ. π. Ἀλ. 33, 1.