Adversary of the Gnostics
- Doctrine of Christ’s Incarnation, Union of Natures, and Recapitulation theory of Atonement.
- The church is one and universal, and it confesses one and the same faith throughout the world. The common faith is confessed at baptism, at which one act the believer receives forgiveness of sins and the Holy Spirit.
- “Canon of truth” referred to the “rule of faith”, the content of the apostolic preaching in summary form that served as a norm for interpreting Scripture and determining the apostolic faith.
- Took church at Rome as the representative church in his argument for apostolic succession (from one teacher to the next; not, from ordainer to ordained). The apostolic faith was preserved at Rome.
- Affirmed the reality of the physical presence of Christ in the Eucharist against the Gnostic depreciation of material elements.
- Mary, in reversing the disobedience of Eve, found a place in Irenaeus’s doctrine of recapitulation.