Laudator Temporis Acti

Philyllius, fragment 19 Kassel and Austin, tr. Ian C. Storey in Fragments of Old Comedy (Cambridge: Harvard University Press, 2011), vol. III, p. 35:

I pray that I may draw a lifesaving breath. This is the most important element of health, to breathe clean and unpolluted air.

ἕλκειν τὸ βέδυ σωτήριον προσεύχομαι,
ὅπερ μέγιστόν ἐστιν ὑγιείας μέρος,
τὸ τὸν ἀέρ' ἕλκειν καθαρόν, οὐ τεθολωμένον.

βέδυ is a rare word, occurring in Clement of Alexandria, Stromata 5.46-48 (tr. Alexander Roberts and James Donaldson):

...it is said that the Phrygians call water Bedu, as also Orpheus says:—

"And bright water is poured down, the Bedu of the nymphs."

Dion Thytes also seems to write similarly:—

"And taking Bedu, pour it on your hands, and turn to divination."

On the other hand, the comic poet, Philydeus [sic, corrected by Casaubon to Philyllius], understands by Bedu the air, as being (Biodoros) life-giver, in the following lines:—

"I pray that I may inhale the salutary Bedu,
Which is the most essential part of health;
Inhale the pure, the unsullied air."

In the same opinion also concurs Neanthes of Cyzicum, who writes that the Macedonian priests invoke Bedu, which they interpret to mean the air, to be propitious to them and to their children.

....

And Apollodorus of Corcyra says that these lines were recited by Branchus the seer, when purifying the Milesians from plague; for he, sprinkling the multitude with branches of laurel, led off the hymn somehow as follows:—

"Sing Boys Hecaergus and Hecaerga."

And the people accompanied him, saying, "Bedu, Zaps, Chthon, Plectron, Sphinx, Cnaxzbi, Chthyptes, Phlegmos, Drops."

See D. Detschew, "Béδu als makedonischer Gott," Glotta 16 (1928) 280-285, who (at 283) conjectured τὸ ναερὸν (a supposedly uncontracted form of the adjective ναρός = flowing) for τὸ τὸν ἀέρ'.