In his sixth satire, Juvenal deplores the pastimes of Roman women, foremost of which is superstition. Speculating about how wives busy themselves while their husbands are away, the poet introduces a revolving door of visitors who include a eunuch of the eastern goddess Bellona, an impersonator of Egyptian Anubis, a Judean priestess, and Chaldean astrologers. From these religious experts women solicit services ranging from dream interpretation and purification to the coercion of lovers or wealthy acquaintances. Juvenal's catalogue captures not only the popularity of these "freelance" experts at the turn of the second century, but also their familiarity among his Roman audiences, whom he could expect to get the joke. Heidi Wendt investigates the backdrop of this enthusiasm for exotic wisdom and practices by examining the rise of self-authorized experts in religion during the first century of the Roman Empire. Unlike members of civic priesthoods and temples, freelance experts had to generate their own legitimacy, often through demonstrations of skill and learning out on the streets, in marketplaces, and at the temple gates.

While historically these professionals have been studied separately from the development of modern conceptions of religion, Wendt argues that they, too, participated in a highly competitive form of religious activity from which emerged the modern-day characters not just of religious experts but specialists of philosophy, medicine, and education as well. Wendt notes affinities across this wider class of activity, but focuses on those experts who directly enlisted gods and similar beings. Over the course of the first century freelance experts grew increasingly influential, more diverse with respect to the skills or methods in which they claimed expertise, and more assorted in the ethnic coding of their wisdom and practices. Wendt argues that this class of religious activity engendered many of the innovative forms of religion that flourished in the second century, including but not limited to phenomena linked with Persian Mithras, the Egyptian gods, and the Judean Christ. The evidence for self-authorized experts in religion is abundant, but scholars of ancient Mediterranean religion have only recently begun to appreciate their impact on the Empire's changing religious landscape.

At the Temple Gates integrates studies of Judaism, Christianity, mystery cults, astrology, magic, and philosophy to paint a colorful portrait of religious expertise in early Rome.