Plato, Letters 362a

ἀνάλωμα, ὃ δʼ ἂν μὴ δύνωμαι, σὴν εἶναι τὴν δαπάνην.τὸ δὴ μετὰ ταῦτα λέγω περὶ τῶν σῶν αὖ χρημάτων τῶν Ἀθήνησιν τῆς ἀναλώσεως, ὅτι πρῶτον μὲν ἐάν τι δέῃ ἐμὲ ἀναλίσκειν εἰς χορηγίαν ἤ τι τοιοῦτον, οὐκ ἔστι σοι ξένος οὐδεὶς ὅστις δώσει, ὡς ᾠόμεθα, ἔπειτα καὶ ἄν τι σοὶ αὐτῷ διαφέρῃ μέγα, ὥστε ἀναλωθὲν μὲν ἤδη ὀνῆσαι, μὴ ἀναλωθὲν δὲ ἀλλʼ ἐγχρονισθὲν ἕως ἄν τις παρὰ σοῦ ἔλθῃ, βλάψαι, πρὸς τῷ χαλεπῷ τὸ τοιοῦτόν σοί ἐστιν καὶ αἰσχρόν. ἐγὼ

that is beyond my power, the charge must fall upon you. In the next place, as regards the spending of your own money at Athens, I have to tell you, first of all, that, contrary to what we supposed, you have not a single friend who will advance money in case I am required to spend something on furnishing a chorus or the like; and further, if you yourself have some urgent affair on hand in which prompt expenditure is to your advantage, whereas it is to your disadvantage to have the expenditure deferred until the arrival of a messenger from you, such a state of affairs is not only awkward but reflects also on your honor. And in fact I discovered this myself