Cicero to his correspondent of the moment — the salutation in the manuscript is corrupt (†CANINI SALVSTIO PROQ.), and editors have generally identified the addressee as C. Caelius Caldus, then serving as proquaestor with Bibulus in Syria. The Perseus dateline gives Tarsus, a.\ d.\ xvi K. Sext. a. 704 (50), that is, the sixteenth day before the Kalends of August — 17 July 50 BC — “or shortly after,” written from Tarsus as Cicero is preparing to depart the province at the end of his year. The letter is the considered reply to two of Caelius’s: technical, deliberate, methodically numbered through six topics, with one personal remonstrance reserved for the close.

The first half of the letter is administrative in temper. Cicero has heard nothing of a successor and plans to step down on the day he arrived: the Parthian alarm has lifted, the legions decreed for Syria will not now march, Marius (his successor designate, if any) is being held to come up only with the legions. He will not linger; he will perhaps stop at Rhodes for the sake of the two boys (his son Marcus and his nephew Quintus); he wants Rome as soon as possible. Then in turn: the rendering of accounts under the Julian law (Cicero advises Caelius to render them, whatever Bibulus does); the controversy of the Apamea garrison, which was withdrawn when the Parthian fear was lifting and which Caelius thinks should have been kept; the quaestor’s accounts and Cicero’s careful handling of public money; the question of three hundred and thirty-three thousand drachmas, on which Cicero firmly declines to oblige Caelius; the legions; and Marius. It is the cool prose of a man closing his books.

The closing section — the second of Caelius’s two letters answered — shifts the temperature. Caelius has asked Cicero to commend him as warmly as possible to Bibulus, his praetor. Cicero will do so, but he uses the occasion for a measured complaint: Caelius alone, of all those around Bibulus, has never warned Cicero of how venomously Bibulus speaks of him. Cicero rehearses Bibulus’s pettiness: refusing to write to Cicero about the Parthian war though the danger touched him; writing only about his son’s augurate; in his dispatches to the Senate, claiming Cicero’s measures as his own and shrugging off shared ones as Cicero’s; insulting Ariobarzanes (whom the Senate, through Cicero, had named king) by addressing him in the despatches only as “son of King Ariobarzanes.” The letter to Bibulus will be written; Caelius can do with it what he likes. The acidity of these lines toward Bibulus — earlier a political rival, now a fellow proconsul whose incompetence has shadowed the eastern command — is the kind of private accounting Cicero generally reserves for Atticus; here he lets a younger man see it, in proportion to a younger man’s request.