FIDES. The Roman goddess Fides is the personification of an idea that in itself is secular: the idea of "confidence" (fides) and, especially (in a more derivative sense of fides), the "good faith" or "trustworthiness" that inspires confidence. Fides made her appearance in the Roman pantheon in the third century CE, about 250, when a temple was dedicated to her by A. Atilius Calatinus. This temple stood on the Capitol, directly next to the temple of Jupiter. But there must have been an earlier sanctuary of Fides (tradition says the cult was established by Numa, the second king of Rome), and the temple built by Calatinus was probably erected on the same site.

The site of the temple of Fides, next to that of Jupiter, is indicative of her origin, for everything points to her having emerged from the supreme deity by a process of hypostatization. In this light...