Правило 75
About the prohibition of indecent church singing.
We wish that those who come to sing in church do not let out disorderly cries, do not force their nature to scream, and do not add anything indecent and unusual for the Church, but with great attention and tenderness offer up psalmody to God, who looks at the hidden. For the sacred word taught the children of Israel to be reverent (Lev. 15:31).
Greek original
Τοὺς ἐπὶ τῷ ψάλλειν ἐν ταῖς ἐκκλησίαις παραγινομένους, βουλόμεθα μήτε βοαῖς ἀτάκτοις κεχρῆσθαι, καὶ τὴν φύσιν πρὸς κραυγὴν ἐκβιάζεσθαι, μήτε τι ἐπιλέγειν τῶν μὴ τῇ ἐκκλησίᾳ ἁρμοδίων τε καὶ οἰκείων· ἀλλὰ μετὰ πολλῆς προσοχῆς καὶ κατανύξεως, τὰς ψαλμῳδίας προσάγειν τῷ τῶν κρυπτῶν ἐφόρῳ Θεῷ. Εὐλαβεῖς γὰρ ἔσεσθαι τοὺς υἱοὺς Ἰσραὴλ τὸ ἱερὸν ἐδίδαξε λόγιον.
Parallel canons
Лаод.15