Patristics – the study of early Christianity in the period stretching from the end of the New Testament to the early Middle Ages – is a foundational discipline for theology. It studies the time in which Christianity as we now know it was formed. First, and most importantly, the canon of Scripture was established as the focus for every aspect of Christian belief, life and practice; the overarching structure of the Christian faith was identified – from creation to the last judgment; rules, creeds and sacramental rites emerged to defend and express this faith; the Christian Church evolved from being a persecuted group to being the Church adopted by the Roman Emperor – and eventually, the Empire. It was also the time when the Church’s ministry, liturgy, calendar and feasts took the shape we are now familiar with today. It is therefore a time of exciting transformations: from the amorphous group of disciples who gathered at Pentecost to confident Christian bishops and theologians, with spiritual, as well as social and political authority; from paganism to Christianity; from classical culture to an emerging Christian culture; from a marginalized sect to the Imperial Church. This is the period before the Church divided. It’s unity, however, comprehended an extraordinarily diverse, immensely rich, cultural, artistic and linguistic heritage, seen in the first Christian hymns and poetry; mosaics and frescos; theological, devotional, spiritual works in languages such as Greek, Latin, Syriac, Aramaic, Coptic, Armenian and Georgian. Above all, Patristics studies the works of those for whom Christianity was a living faith: one they preached, prayed and practiced as bishops and pastors, in often hostile and challenging circumstances, rather than as academic theologians. We have much to learn from it as scholars, church members, and Christians in the world.