Honorius I (died October 12, 638) was pope from 625 to 638.

He became pope on October 27, 625, two days after the death of his predecessor, Boniface V. The festival of the Elevation of the Cross is said to have been instituted during the pontificate of Honorius, which was marked also by considerable missionary enterprise. Honorius in his lifetime had favoured the formula proposed by the emperor Heraclius with the design of bringing about a reconciliation between the Monophysites and the Catholics, which bore that Christ had accomplished His work of redemption by one manifestation of his will as the God-man. For this he was, more than forty years after his death, anathematized by name along with the other Monothelite heretics by the Council of Constantinople (First Trullan ) in 680; and this condemnation was subsequently confirmed by more than one pope, particularly by Leo II as has been abundantly proved by unimpeachable evidence against the contentions of Baronius and Bellarmine. This anathema was later one of the main arguments against Papal infallibility in the discussions surrounding the First Vatican Council of 1870.

Original text taken from a paper copy of the 9th edition Encyclopædia Britannica (1881)