Irenaeus' theology of the Holy Spirit is often highly regarded amongst theologians today, but that regard is not universal, nor has an adequate volume of literature supported it. This study provides a detailed examination of certain principal, often distinctive, aspects of Irenaeus' pneumatology. In contrast to those who have suggested Irenaeus held a weak conception of the person and work of the Holy Spirit, Anthony Briggman demonstrates that Irenaeus combined Second Temple Jewish traditions of the spirit with New Testament theology to produce the most complex Jewish-Christian pneumatology...