To Augustus Gratian three books "On the holy spirit". Book 1

The article contains information about the composition of St. Ambrose of Milan “On the Holy Spirit” (“De Spiritu Sancto”), written at the request of Emperor Gratian in 381 A.D. Through the prism of triadological doctrines tractate describes the doctrine of the Third Person of the Holy Trinity. The article introduces the first publication of the translation of the first book into Russian. Maxim Gennadievich Matsegora is a Graduate of the Saint Petersburg Orthodox Theological Seminary. Saint Ambrose of Milan. To Augustus Gratian Three Books On the Holy Spirit. Book 1 The tractate “On the Holy Spirit” is the only of three main dogmatic compositions by St. Ambrose of Milan (“On Faith”, “On the Holy Spirit”, “On the Mystery of the Lord Embodiment”) that is still not known to the Russian reader. The theme of Pneumatology disclosed in this essay is an urgent and in need of additional study area of dogmatic theology. The contents of the tractate also addresses the historical realities of the Church life in the late of IV century. It is the first publication if the work’s first book translated into Russian from Latin by M.G. Matsegora.