The term "pauperes Christi" has been in use for centuries. From the beginning it meant the involuntary poor, the indigent who had no money or property, who depended upon others for their sustenance, who were on the rolls of a certain church and cared for by that church. In Carolingian times "the poor of Christ" embraced widows and orphans as well as indigents, all of whom made up a sort of special class of people to be protected by the law and supported by the Church. Thus, Jacques de Vitry in the thirteenth century referred to all the poor, the sick, the wretched, the starving, lepers, etc. as pauperes Christi. In other words, pauperes Christi refers to the little people, those called anawim in the Old Testament, for that is exactly what pauper means: one who has produced [peperit] little [paucum], one who is considered a person of little worth.

From the beginning, however, "poor of Christ" possessed within it the seeds of ambiguity. It could extend to a spiritual reality that went beyond the vulnerability of economic poverty. "Poor of Christ" became a title for monks, the voluntary poor, whose communities might or might not be poor. In the eleventh century the term also included individual hermits, in the twelfth century canons regular (clerics who lived in community according to the Rule of Saint Augustine and served the apostolic needs of the local Church), and in the early thirteenth century a community of Carthusians.

The Cistercians who, like the Carthusians, had adopted a very strict form of poverty, also call themselves "the poor of Christ" in their early documents. Saint Bernard adds the significant word servus [servant, slave], calling himself "the servant of Christ's poor at Clairvaux". Guigo I, the fifth Carthusian prior after Bruno, also links servus with pauper (although he does not join either word with Christi). He calls himself "the useless servant of the poor Carthusians", and he calls the community the pope's "poor servants and sons at La Chartreuse". In the Carthusians and Cistercians the terms indicate both a counter-cultural attitude and a profound acceptance of the status of anawim. The fact that servitio [service] appears along with pauperes Christi sacerdotes in the first cum clause of Cum ex plurium intimates that pauperes Christi applies as a technical term to the companions. It contains the idea of service of Christ through renunciation, and is linked with the adage of St. Jerome, "naked, follow the naked Christ". This is certainly what the companions had in mind to do. In this respect Ignatius and his companions are very much in line of these two renewal movements, the Carthusians and the Cistercians.

The twelfth and thirteenth centuries saw a burst of renewal activity centering on poverty, most of it coming from lay people, some of it orthodox and some quite unorthodox, all of it an attempt to imitate the simplicity of life of the apostles and the early Church. In France the Waldensians or Poor men of Lyons called themselves "poor of Christ" but strayed from the path of orthodoxy. The poor Catholics of Durand de Huesca in southern France and Spain, and the Humiliati in northern Italy (Lombardy), both groups drawn from the Waldensians in order to convert them, eventually foundered but helped prepare the way for the Friars Minor, the Poor Clares, and the Dominicans. Even the Cathars, for different reasons, called themselves "poor of Christ". All these people lived actual poverty.

Bonaventure calls Francis "the poor man of Christ" [Christi pauper], and Francis calls all his followers "poor men of Christ". The term does not appear in the Dominican tradition, but the  reality does, for Dominicans follow the apostolic life that Augustine chose, which is "to leave everything for the sake of Christ and to preach him while serving him in poverty". Whereas the Franciscans were a part of the poverty movement and differed from other groups by reason of their orthodoxy and fidelity to the Church, the Dominicans stood over against those of heretical bent even though they adopted the poverty found amongst their adversaries. They were not part of the poverty movement, but were the vanguard of a preaching movement that saw poverty as a guarantee of fidelity to the Gospel.