This book offers collected and in translation, a series of texts sufficiently representative of the formation and development of Christian thought in the early centuries of the Church. The selection may be of interest and use to the many people who care about the deep historical roots of Christian thought, and perhaps the time has, facilities philological literature or preparing to go directly to the best editions of his sources. The need to keep the book in hand proportions, has given preference to those texts and authors that are more representative from the standpoint of what became a common dopctrina Church. Have been preferred, therefore, those authors who most influenced later Christian thinking. This selection has been closed with Athanasius. This compilation, with its four indices will be a useful working tool for anyone interested in theological studies and may serve as an incentive to read the original works in their entirety.