ὑποσχέσθαι
From LSJ
ἀλλήλων τὰ βάρη βαστάζετε, καὶ οὕτως ἀναπληρώσετε τὸν νόμον τοῦ Χριστοῦ → bear each other's burdens, and in that way fulfill the anointed King's Law (Galatians 6:2)
English (LSJ)
A v. ὑπισχνέομαι.
Greek (Liddell-Scott)
ὑποσχέσθαι: ἴδε ὑπισχνέομαι.
French (Bailly abrégé)
inf. ao.2 de ὑπισχνέομαι.