Now most would suggest that what Paul was talking about were saints in the familia Caesaris—an entity commonly defined as the collectivity of the emperor’s slaves and freedmen in the imperial bureaucracy spread throughout the Roman world. There is also a growing consensus that Paul did not write Philippians from Rome, but from the province of Asia, likely from Ephesus (see Flexsenhar, “Provenance of Philippians.”). An Asian provenance for Philippians offers the best answer as to why Paul sent greetings from “saints” in a familia Caesaris to the Philippians and how there was an especially close connection between the two groups. The familia Caesaris of Philippians 4:22 was a particular, local group of imperial slaves. It was a familia of Caesar in Roman Asia, not a reference to a group in Rome or even an empire-wide organization of slaves and freedmen. By delving into the available details about imperial personnel in the Aegean region, and by paralleling those details with information from Paul’s other Aegean contacts, a fresh profile of Paul’s familia Caesaris emerges. In turn, that sketch helps explain how Paul passed on greetings from individual “saints” in that particular familia Caesaris to the Philippian community because the two groups already knew each other. Indeed, the “saints” and individuals in Philippi shared a common cult because they were most likely already connected by kinship and labor networks in the northern Aegean.

For the many tasks involved in such an enterprise, the emperors would put up their personal property and former property in the form of their slaves and freedpersons. Ephesus was “the biggest emporium of Western Asia Minor,” the regional center of a provincial and extraprovincial economy, which the imperial economy intersected. Imperial slaves and freedpersons in Ephesus, first century BCE to first century CE

1. What was “Caesar’s household”?
2. Geo-chronological distribution of imperial slaves and freedpersons in Roman Asia

To begin in broad strokes, the Greek phrase that Paul uses for “Caesar’s household” (Καίσαρος οἰκία) is the direct equivalent of the Latin phrase familia Caesaris. In antiquity, when the Latin phrase familia Caesaris is used, whether in literary or epigraphic sources, it does not designate imperial slaves and freedmen, much less all imperial slaves and freedmen in the bureaucracy. It designates a specific, local group of imperial slaves. In the only detailed ancient description of the familia Caesaris, the late first-century curator of Rome’s aqueducts, Julius Sextus Frontinus (ca. 40–104 CE), portrays the groups of imperial slave workers (familiae Caesaris) who maintained the city’s water ducts as the direct counterparts of the groups of public slave workers (familiae publicae).

1. The key to understanding “Caesar’s household” in Philippians 4:22 is ancient slavery terminology. The identity marker Caesaris/Καίσαρος was the preferred term for individual imperial slaves, whether in the Latin West or Greek East (figs. 2 and 3).
2. Map of the Aegean region, showing Roman provinces, cities of Paul’s mission, and known places of imperial personnel.

One familia Caesaris describe themselves first as a collegium, and then as a “family of our Caesar’s couriers” (familia tabellariorum Caesaris) who reside in Narbo (the present-day port city of Narbonne, France). Another example, from the opposite side of the Mediterranean, that does use the exact Latin familia Caesaris comes, interestingly enough, from Paul’s immediate context in the Aegean. The inscription is from Coela, a city in the province of Thrace (Thracia Chersonesos), near present-day Eceabat, Turkey. The inscription even dates to the early Neronian period, 55 CE to be precise. The slavery terminology employed in the literary and epigraphic comparanda throw much more light on the “Caesar’s household” (familia Caesaris) that Paul mentions. The dimensions of a familia Caesaris were both bureaucratic and domestic. Such familiae were made through connections of substance, eating, living together, procreation, and emotion. Like the groups from Narbo and Coela, the individuals in Paul’s familia Caesaris were associated as a slave familia not just by compulsion, but because they lived and worked together in the same area, had ethnic ties, and shared labor, cults, or family connections.

Paul’s expression Καίσαρος οἰκία does not “naturally” refer to members of Nero’s family, dependent kin of any degree of relationship as well as to household slaves and various retainers, all of which would make up a very large group. Nor does the expression indicate “the imperial service” or the “imperial bureaucracy” as a collectivity. It refers to slaves who worked in a particular part of the broader imperial bureaucracy.And in no way does the reference in Philippians 4:22 favor a Roman provenance for Paul’s letter because the majority of the members of the familia Caesaris would have been stationed in Rome (Holloway, Philippians, 23, 190–91, citing Bockmuehl, Philippians, 30–31, and Weaver, Familia Caesaris, 78–80). House-born slaves (vernae/οἰκογενής) are well attested in the ancient sources, and the material record has left glimpses of this rich social fabric among imperial personnel in first-century Ephesus (See the imperial slave Antiochus from late first-century Athens (fig. 2): AE 1947, 77 = SEG 21.1058. See also SEG 31.1124; MAMA 5.114; MAMA 1.29. House-born slaves: IPOstie A, 279 = ISIS 127. From Ephesus: CIL 3.436 = IvE 6.2210).

1. Sketching a Profile of Paul’s “Caesar’s Household”

The evidence that exists from first-century Ephesus, and certainly from Ephesus in the following century, indicates that imperial slaves were indeed engaged largely in finance related to the imperial treasury (fiscus/φίσκος). In all likelihood, the labor that those from “Caesar’s household” performed, whether in Ephesus or elsewhere in Asia, was in the area of imperial finance. An important clue for deciphering more specifically what kind of work those from “Caesar’s household” did is Erastus from Corinth. Paul mentions the name once (Rom 16:23). Of all the individuals named in Paul’s letters Erastus is the only one to whom Paul attaches any occupational information. He calls Erastus a οἰκονόμος τῆς πόλεως. This occupational phrase indicates that though not an imperial slave, Erastus was a public slave.

The case for an imperial dispensator from first-century Ephesus who is identified as Eutychus Caesaris. His exact financial responsibilities are unknown, but based on the fine workmanship of his cinerary urn (ostotheke) he became quite wealthy. Notably, the majority of inscriptions that vicarii produced come not from Rome, where the majority of imperial slave and freed inscriptions survive, but from the provincial centers of administration and “customs posts,” like Ephesus.

Based on the above comparisons, the “Caesar’s household” that Paul references was likely engaged in financial labor and was probably headed by a dispensator or a vilicus, like Erastus in the public slave system at Corinth.