Moral Letters to Lucilius Section 9

Mira in quibusdam rebus verborum proprietas est et consuetudo sermonis antiqui quaedam efficacissimis et officia docentibus notis signat. Sic certe solemus loqui: ille illi gratiam rettulit. Referre est ultro, quod debeas, adferre. Non dicimus gratiam reddidit, reddunt enim et qui reposcuntur et qui inviti et qui ubilibet et qui per alium. Non dicimus reposuit beneficium aut solvit; nullum nobis placuit, quod aeri alieno convenit, verbum.

C’est chose merveilleuse que la justesse de certaines expressions ; et le génie de l’ancien langage caractérise certains actes en termes si frappants que l’enseignement du devoir y est visiblement marqué. Telle est assurément la locution habituelle : Ille illi gratiam retulit (il a été reconnaissant), ce qui veut dire : il a spontanément rapporté ce qu’il devait. Nous ne disons pas il a rendu ; on rend quand on en est prié, on rend malgré soi, et n’importe où et par intermédiaire. Nous ne disons pas il a remis, il a payé ;

There is a marvellously accurate phraseology applied to certain subjects, a long-established terminology which indicates certain acts by means of symbols that are most efficient and that serve to outline men’s duties. We are, as you know, wont to speak thus: “A. has made a return for the favour bestowed by B.” Making a return means handing over of your own accord that which you owe. We do not say, “He has paid back the favour”; for “pay back” is used of a man upon whom a demand for payment is made, of those who pay against their will, of those who pay under any circumstances whatsoever, and of those who pay through a third party. We do not say, “He has ‘restored’ the benefit,” or ‘settled’ it; we have never been satisfied with a word which applies properly to a debt of money.