Laudator Temporis Acti

To the collection of classical parallels to "Physician, heal thyself," add this fable attributed to Aesop (Chambry 69, tr. Olivia and Ronald Temple):

One day, a frog in a marsh cried out to all the animals: 'I am a doctor and I know all the remedies!' A fox, hearing this, called back: 'How could you save others when you can't even cure your own limp?'

This fable shows that if one isn't initiated into a science one ought not to instruct others.

Ὄντος ποτὲ βατράχου ἐν τῇ λίμνῃ καὶ τοῖς ζώοις πᾶσιν ἀναβοήσαντος· Ἐγὼ ἰατρός εἰμι φαρμάκων ἐπιστήμων, ἀλώπηξ ἀκούσασα ἔφη· Πῶς σὺ ἄλλους σώσεις, σαυτὸν χωλὸν ὄντα μὴ θεραπεύων; Ὁ μῦθος δηλοῖ ὅτι ὁ παιδείας ἀμύητος ὑπάρχων, πῶς ἄλλους παιδεῦσαι δυνήσεται;

Babrius versified this as follows (tr. Ben Edwin Perry):

That denizen of the swamps who likes the shade, the frog, who lives beside the ditches, once came forth on dry land and bragged to all the creatures: "I'm a physician, skilled in the use of drugs such as no one, doubtless, knows, not even Paean who lives on Olympus, physician to the gods." "And how, said a fox, "can you cure someone else, when you can't save yourself from being so deadly pale?"

Ὁ τελμάτων ἔνοικος ὁ σκιῇ χαίρων,
ὁ ζῶν ὀρυκτοῖς βάτραχος παρ' αὐρίποις,
εἰς γῆν παρελθὼν ἔλεγε πᾶσι τοῖς ζώοις·
"ἰατρός εἰμι φαρμάκων ἐπιστήμων,
οἵων ταχ' οὐδεὶς οἶδεν, οὐδ' ὁ Παιήων,
ὃς Ὄλυμπον οἰκεῖ καὶ θεοὺς ἰατρεύει."
"καὶ πῶς" ἀλώπηξ εἶπεν "ἄλλον ἰήσῃ,
ὃς σαυτὸν οὕτω χλωρὸν ὄντα μὴ σώζεις;"

Babrius followed a variant of Aesop's fable where the frog was χλωρὸν (green, pallid), not χωλὸν (lame). Aphthonius 24 and Avianus 6 likewise refer to the frog's color, not its gait. Cf. Genesis Rabbah 23 [15c]: "Physician, heal your own lameness."