The preservation of Philo’s writings was significantly influenced by early Christian figures like Eusebius of Caesarea, who interpreted Philo’s descriptions in a way that aligned with Christian interests. Let’s break this down:

1. Eusebius and the Therapeutae as Christians:

Eusebius of Caesarea (c. 260–340 CE) in his *Ecclesiastical History* (Book II, Chapter 17) suggested that the Therapeutae and Therapeutrides, described by Philo in *On the Contemplative Life*, were early Christians, possibly even a Christian monastic community. Philo, a Jewish philosopher from Alexandria (c. 20 BCE–50 CE), described these groups as ascetic Jewish communities near Lake Mareotis, devoted to prayer, study, and contemplation. Eusebius interpreted their practices—such as communal meals, scriptural study, and asceticism—as resembling Christian monasticism, leading him to claim they were Christians. This interpretation likely contributed to the Christian interest in preserving Philo’s works, as they were seen as documenting an early proto-Christian group.

This connection made Philo’s writings valuable to early Christians, who copied and transmitted his texts in monastic and ecclesiastical settings, ensuring their survival when many other Hellenistic Jewish works were lost.

2. Eusebius and the Legend of Philo Meeting Peter:

Eusebius also promoted a tradition that Philo met the Apostle Peter in Rome during the reign of Emperor Claudius (41–54 CE). In *Ecclesiastical History* (Book II, Chapter 17), Eusebius suggests Philo interacted with early Christians and was impressed by their piety, specifically linking him to the Christian community in Rome. This claim is not corroborated by Philo’s own writings or other contemporary sources and is widely considered a legend by modern scholars, likely constructed to bridge Jewish and Christian intellectual traditions.

This narrative further elevated Philo’s status among Christians, reinforcing the preservation of his works by framing him as a figure sympathetic to Christianity.

3. Jerome Listing Philo as a Church Father:

Jerome (c. 345–420 CE), in his work *De Viris Illustribus* (On Illustrious Men, Chapter 11), includes Philo among notable Christian writers, describing him as a Jewish scholar who wrote extensively and was respected by Christians. While Jerome does not explicitly call Philo a “Church Father” in the formal sense, his inclusion in this catalog of significant Christian figures suggests a perception of Philo as a quasi-Christian or at least a figure whose works were theologically valuable. This further cemented the Christian appropriation of Philo’s writings.

Why This Matters:

Philo’s works, particularly his allegorical interpretations of the Hebrew Scriptures, were highly compatible with early Christian exegesis, especially in the Alexandrian school (e.g., Clement and Origen). His philosophical synthesis of Judaism and Platonism provided a framework that Christians found useful for articulating their theology.

The misidentification of the Therapeutae as Christians, combined with legends like Philo’s meeting with Peter, made Philo a bridge figure between Judaism and Christianity. This led to his texts being preserved in Christian contexts, particularly in monasteries, when many other Jewish texts from the Second Temple period were not.

Scholarly Consensus:

Modern scholars, such as those cited in works like David Runia’s *Philo in Early Christian Literature* (1993), agree that Eusebius’ claims about the Therapeutae and Philo’s Christian connections are likely anachronistic and apologetic, aimed at legitimizing Christian asceticism and intellectual traditions by linking them to a respected Jewish philosopher.

There is no definitive evidence that Philo met Peter or that the Therapeutae were Christians. Philo’s own writings present the Therapeutae as a Jewish sect, and his works show no direct engagement with Christian ideas.

In summary, Eusebius’ identification of the Therapeutae as Christians and his promotion of the legend that Philo met Peter in Rome significantly contributed to the Christian preservation of Philo’s writings. Jerome’s inclusion of Philo in his catalog further reinforced this, though calling him a “Church Father” is a slight exaggeration of Jerome’s stance. These factors ensured Philo’s works survived through Christian scribal traditions.