Eduard Verhoef suggests that the church numbered around 33 in the AD 60s. He arrives at this number by noting that, “All in all we can list 11 people who had chosen to go the way indicated by Paul: Lydia, the goaler [sic, jailer], two bishops, two deacons, Epaphroditus, Eudia, Syntyche, the ‘companion’ and Clement.”
He also then notes, “The 11 people mentioned above will have belonged to different families. The average family may have consisted of two parents, two children and two slaves. Let us say that half of those people comprised the congregation, there were 11 x 3 = 33 members of the congregation. Verhoef is cautious about the number, noting the uncertainties and hypothetical nature of the data. But he also suggests that 33 is “defendable.” Eduard Verhoef, Philippi: How Christianity Began in Europe: The Epistle to the Philippians and the Excavations at Philippi (London: Bloomsbury, 2013), 21–22.