Plato, Laws 882b

δὲ παραλαβών, δήσας ἐν πέδαις καὶ μαστιγώσας ὁπόσας ἂν ἐθέλῃ, μηδὲν βλάπτων τὸν δεσπότην, παραδότω ἐκείνῳ κεκτῆσθαι κατὰ νόμον. ὁ δὲ νόμος ἔστω· ὃς ἂν ἐλεύθερον δοῦλος ὢν τύπτῃ μὴ τῶν ἀρχόντων κελευόντων, παραλαβὼν ὁ κεκτημένος παρὰ τοῦ πληγέντος δεδεμένον αὐτὸν μὴ λύσῃ,

shall bind the slave, and hand him over to the injured person, and he shall take charge of him and bind him in fetters, and give him as many stripes with the scourge as he pleases, provided that he does not spoil his value to the damage of his master, to whose ownership he shall hand him over according to law. The law shall stand thus:—Whosoever, being a slave, beats a free man without order of the magistrates,—him his owner shall take over in bonds from the person assaulted, and he shall not loose him until the slave have convinced the person assaulted that he deserves to live