Since the 1960s, Colombia has been the theatre of multiple armed conflicts that, one way or another, have involved all sectors of society. Colombian religious actors, including the Catholic Church, in particular, have historically played an ambivalent role in the conflict. While some Catholic clerics have ideologically supported, aided and abetted, or even joined state and non-state armed actors especially during the first decades of the conflict, since the 1980s the Colombian Catholic Church has progressively been assuming a posture in favour of peace either through action or discourse. Most recently, these praxes have culminated in the participation of the Catholic Church in most of the high-level negotiations between the Colombian state and non-state armed groups (NSAGs). The scholarship exploring the Church’s influential role in these peacebuilding and mediation efforts in Colombia has begun to burgeon only in the past twenty-five years. However, this literature has left largely unaddressed questions around the influence that the Catholic Church has had on the parties to the conflict. Such questions may help explain how the Church, as an institution, was able to garner the legitimacy necessary to become a key mediator between the state and NSAGs. Building on the data gathered and the framework elaborated as part of the Generating Respect Project (GRP), this article explores how the Church’s legitimacy was constructed from the bottom, by both leveraging affinities with armed groups’ ideologies and the impact of local initiatives aimed at protecting the civilian population in the midst of the armed conflict.