Marcus Grodi and Msgr. Jeffrey Steenson continue their study of Against Heresies, written by St. Irenaeus of Lyons in the 2nd century.

Continuing through Book V, they look at what St. Irenaeus has to say about the necessity of the Church, the nature of the Godhead, and the role of Mary in the plan of salvation. Though St. Irenaeus is writing long before the word “Trinity” is adopted by the Church, he looks at the relationship between Father, Son and Spirit, and the implications of that relationship for salvation history and the life of the Church.