Clerics and monks were originally chalk and cheese. The clergy were an increasingly complex system committed to highly structured hierarchy – but there were unresolved uncertainties about the precise form it should take. The chapter discusses for instance the clerical cursus honorum, reactions against fast-track promotion, and the bigamia rule against clerics in higher orders marrying more than once and the rule’s relation to pagan marriage. The apostolic see was called in to clarify problems arising from these systems and also from the awkward relation between clerics and monks. Monasticism was an unstructured movement, sometimes out of control, at one point banned from towns by imperial law. The interpenetration of the clerical and monastic systems only intensified the challenge of integrating them. The problem would recur in different forms throughout the history of the Latin Church, and the difficulty of coordinating the two overlapping systems had the unintended consequence of strengthening the papacy, constantly called in to integrate monks within the religious legal system and adjust the differences between the two religious elites. The process is already in evidence with the earliest papal jurisprudence.

In late Antiquity there were too many hierarchies for comfort. How to coordinate them was not self-evident. This chapter looks at the apostolic see’s efforts to resolve a case where imperial law clashed with episcopal law, to regulate relations between the imperial and episcopal hierarchy (in which the bishop of Rome was included), and to coordinate hierarchy of command with status hierarchy. Indissolubility of marriage (papal versus imperial rulings), the ban on members of the curial class entering the clergy, and metropolitan episcopal jurisdiction are discussed.

Penance was a possibility for returning heretics and for other sinners too. As is well known, the penitential system was quite different from what developed subsequently, key features being that the penance was public, marking reinsertion into the community, and that it could be done only once, though anyone could be forgiven at the point of death. Again, practical problems arose: could the clergy do penance? Could one return after penance to professions with a high risk of sin, given the unrepeatability of the ritual? Such practical problems are reflected in the early decretals.

The celibacy within marriage of the secular clergy may have been a response to the celibacy of monks, because monks were becoming prominent in Western Christianity in the fourth century. Originally lay, without clerical orders, their relation to the ordinary clergy, while not hostile, was complicated and problematic from the start. What happened when clerics became monks or vice versa, for instance? Dealing with the interactions of these two elites would be a central role of the papacy ever afterwards. In the early papal legislation we see the start of this mediating role.