Aesop, Fab. 54 (Perry=Chambry 172) Boy and Snails
“A farmer’s child was roasting snails. When he heard them trilling as they cooked, he said, “Most pathetic creatures, You are singing as your homes burn?”
This story makes it clear that everything done at the wrong time should be mocked.”
γεωργοῦ παῖς κοχλίας ὤπτει. ἀκούσας δὲ αὐτῶν τριζόντων ἔφη· „ὦ κάκιστα ζῷα, τῶν οἰκιῶν ὑμῶν ἐμπιπραμένων αὐτοὶ ᾄδετε;”
ὁ λόγος δηλοῖ, ὅτι πᾶν τὸ παρὰ καιρὸν δρώμενον ἐπονείδιστον.
This looks like it has jumped to a proverb in Modern Greek which attributes it to Thucydides and changes the person of the verb, rendering it. “you sing while your homes are burning.” [«Των οικιών ημών εμπιπραμένων, ημείς άδομεν»]. I retweeted thinking it did not sound much like the ancient historian, but just had to check for it.
https://twitter.com/Andreas50805488/status/1161574040554868736?s=20
So, I think this qualifies on my rating scale as Delphian Graffiti Fake: It has antiquity, but has been reassigned for authority in a new context. I mean, really, who wants to cite Aesop and his animals when we have the gravity of Thucydides. And, let’s be honest, this is a good line for any age, but especially apt for ours.

Here’s some singing about burning down a house:
Anonymous, Greek Anthology, 7.704 [=see here for more]
“When I’m dead, the earth can be fucked by fire.
It means nothing to me since I’ll be totally fine.”
Ἐμοῦ θανόντος γαῖα μιχθήτω πυρί·
οὐδὲν μέλει μοι· τἀμὰ γὰρ καλῶς ἔχει.