Deuteronomy 15:17

καὶ λήμψῃ τὸ ὀπήτιον καὶ τρυπήσεις τὸ ὠτίον αὐτοῦ πρὸς τὴν θύραν καὶ ἔσται σοι οἰκέτης εἰς τὸν αἰῶνα καὶ τὴν παιδίσκην σου ποιήσεις ὡσαύτως