These are the only three existing ante-Nicene treatises on the Lord’s Prayer. Candidates for baptism in the ancient Church were trained in prayer, a practice that gave rise to a tradition of commentary on the Lord’s Prayer. These classic texts became the starting points for many other commentaries. Of the three, however, only the discourse of Cyprian is an address to catechumens. Tertullian’s treatise contains additional material on the conduct of worship and on prayer in the assembly, and Origen’s commentary is a vast work on the whole subject of prayer, as much suited to advanced learners in the school of Christ as to those preparing for baptism. All these texts remain spiritually vital, but since they are addressed to a different world, the translator has provided brief notes on points of difficulty and accessible yet scholarly introductions to make these rich works available to a fresh audience.