Plato, Laws 828c

ἑορτὰς εἶναι τοῖς δώδεκα θεοῖς, ὧν ἂν ἡ φυλὴ ἑκάστη ἐπώνυμος ᾖ, θύοντας τούτων ἑκάστοις ἔμμηνα ἱερά, χορούς τε καὶ ἀγῶνας μουσικούς, τοὺς δὲ γυμνικούς, κατὰ τὸ πρέπον προσνέμοντας τοῖς θεοῖς τε αὐτοῖς ἅμα καὶ ταῖς ὥραις ἑκάσταις, γυναικείας τε ἑορτάς, ὅσαις χωρὶς ἀνδρῶν προσήκει καὶ ὅσαις μή, διανέμοντας. ἔτι δὲ καὶ τὸ τῶν χθονίων καὶ ὅσους αὖ θεοὺς οὐρανίους ἐπονομαστέον καὶ τὸ τῶν τούτοις ἑπομένων οὐ συμμεικτέον ἀλλὰ χωριστέον, ἐν τῷ τοῦ Πλούτωνος

to each of these they shall perform monthly sacrifices and assign choirs and musical contests, and also gymnastic contests, as is suitable both to the gods themselves and to the several seasons of the year; and they shall ordain also women’s festivals, prescribing how many of these shall be for women only, and how many open also to men. Further, they must determine, in conformity with the law, the rites proper to the nether gods, and how many of the celestial gods should be invoked, and what of the rites connected with them should not be mingled but kept apart, and put them in the twelfth month,