John Chrysostom favored a cappella singing in worship and opposed the use of musical instruments. It must be stated, however, that John's opposition to musical instruments was something he applied to every area of life, not only their use in worship. For him, musical instruments were of the devil. Here are three specimen citations from him on the subject. It's been my habit for years to make a record of citations to document my on-going hobby of studying early church writers, and thought that some of you might find these comments from him interesting. John Chrysostom (349-407): Let them make melody on drum and harp. Some commentators also take the mention of these instruments in a spiritual sense and say that the drum implies the mortification of our flesh, while the harp has reference to heaven, this instrument being played on high, not here below, like the lyre. I say this, on the other hand, that in ancient times they were led by these instruments owing to the dullness of their thinking and their recent conversion from idols. So, just as he permitted them sacrifices, in like manner he also let them have these things, out of considerateness for their limitations. Robert Charles Hill, trans., St John Chrysostom: Commentary on the Psalms, Vol. 2, Psalm 149 (Brookline: Holy Cross Orthodox Press, 1998), p. 367. Greek text: Τινὲς μὲν καὶ τούτων τῶν ὀργάνων τὸν λόγον κατὰ ἀναγωγὴν ἐκλαμβάνοντες, λέγουσιν ὅτι τὸ μὲν τύμπανον τὴν νέκρωσιν τῆς σαρκὸς ἡμῶν ἐπιζητεῖ, τὸ δὲ ψαλτήριον τὸ πρὸς τὸν οὐρανὸν βλέπειν. Καὶ γὰρ ἄνωθεν τὸ ὄργανον τοῦτο κινεῖται, οὐ κάτωθεν, ὥσπερ ἡ κιθάρα. Ἐγὼ δὲ ἐκεῖνο ἂν εἴποιμι, ὅτι τὸ παλαιὸν οὕτως ἤγοντο διὰ τῶν ὀργάνων τούτων, διὰ τὴν παχύτητα τῆς διανοίας αὐτῶν, καὶ τὸ ἄρτι ἀπεσπάσθαι ἀπὸ τῶν εἰδώλων. Ὥσπερ οὖν τὰς θυσίας συνεχώρησεν, οὕτω καὶ ταῦτα ἐπέτρεψε, συγκαταβαίνων αὐτῶν τῇ ἀσθενείᾳ. In Psalmum CXLIX, PG 55:494. John Chrysostom (349-407): Where pipers (αὐληταὶ) are, by no means there is Christ. NPNF1: Vol. XIII, Homilies on the Epistle of St. Paul to the Colossians, Homily 12. Greek text: Ἔνθα αὐληταὶ, οὐδαμοῦ ὁ Χριστός· In epistulam ad Colossenses, Homilia XII, §6 PG 62:389. John Chrysostom (349-407) on weddings: For dancing, and cymbals, and flutes, and shameful words, and songs, and drunkenness, and revellings, and all the Devil’s great heap (πολὺς ὁ τοῦ διαβόλου φορυτός) of garbage is then introduced. NPNF1: Vol. XII, Homilies on First Corinthians, Homily 12.5. Greek text: Καὶ γὰρ χορεῖαι καὶ κύμβαλα καὶ αὐλοὶ καὶ ῥήματα καὶ ᾄσματα αἰσχρὰ καὶ μέθαι καὶ κῶμοι καὶ πολὺς ὁ τοῦ διαβόλου τότε ἐπεισάγεται φορυτός. In epistulam i ad Corinthios, Homilia 12, §5, PG 61:103.