Plato, Laws 887b

ἀλλʼ, ὦ ξένε, πολλάκις μὲν ὥς γε ἐν ὀλίγῳ χρόνῳ τοῦτʼ αὐτὸ εἰρήκαμεν, ὡς οὐδὲν ἐν τῷ παρόντι δεῖ προτιμᾶν βραχυλογίαν μᾶλλον ἢ μῆκος—οὐδεὶς γὰρ ἡμᾶς, τὸ λεγόμενον, ἐπείγων διώκει—γελοῖον δὴ καὶ φαῦλον τὸ πρὸ τῶν βελτίστων τὰ βραχύτερα αἱρουμένους φαίνεσθαι. διαφέρει δʼ οὐ σμικρὸν ἁμῶς γέ πως πιθανότητά τινα τοὺς λόγους ἡμῶν ἔχειν, ὡς θεοί τʼ εἰσὶν καὶ ἀγαθοί, δίκην τιμῶντες διαφερόντως ἀνθρώπων· σχεδὸν γὰρ τοῦτο ἡμῖν ὑπὲρ ἁπάντων

Still, Stranger, we have frequently (considering the shortness of the time) made the very statement,—that we have no need on the present occasion to prefer brevity of speech to lengthiness (for, as the saying goes, no one is chasing on our heels); and to show ourselves choosing the briefest in preference to the best would be mean and ridiculous. And it is of the highest importance that our arguments, showing that the gods exist and that they are good and honor justice more than do men, should by all means possess some degree of persuasiveness;