[4] The Ecthesis would only be seen as an accepted doctrine for two years; the death of Pope Honorius I resulted in a significant reduction in Monothelitism support.
At the time of his election he was a deacon at the Hagia Sophia and feeder of the poor (πτωχοτρόφος) at the Phrixos harbour.
[11] When the emperor's wife Fabia Eudokia died on 13 August 612, Heraclius decided to marry his niece Martina.
Heraclius acknowledged the problem, but decided to marry her anyway, writing to Sergius I that the latter had done his duty "as patriarch and as a friend".
It is possible that given the precarious state of the empire – the Byzantine army under General Heraclius had just suffered a major defeat against the Persians at Antioch in 613 – Sergius I chose to put unity and cooperation with the emperor above the church canon.
[13] In 614, the Persian army seised Jerusalem, damaging the Church of the Holy Sepulchre in the process and capturing the True Cross, originally discovered by the Empress Helena.
The fall of Jerusalem and the loss of the True Cross came as a shock and led to a crusading mood among the empire's populace.
Believing that under these conditions Constantinople was no adequate base for a counteroffensive, Heraclius began to secretly move the empire's gold and financial reserves to Carthage.
Henceforth Sergius I was credited with saving the capital, gaining him significant popularity amongst the populace of Constantinople.
While it is likely that the main executive power rested with Bonus, Sergius I probably played a leading role in discussions.
[19] In June 626 Persian troops appeared before Chalcedon, making camp in expectation of the Avar army.
An attempt at negotiations with the Avar Khagan failed and the main army reached Constantinople on 29 July.
He led a litany to the Hodegetria icon just before the final attack of the Avars, and right after completing it a huge storm crushed the invading fleet, saving Constantinople.
[22] It was rumoured that a previous hymn of the Eastern Orthodox Church was composed in honour of this battle and of Sergius I.
[23] With the victory over the Persians, rifts in the religious society began to emerge again between Monophysite and Chalcedonian beliefs.
It was hoped that the idea would appeal to both Chalcedonians and to Monophysite followers in the empire as it fused basic principles taken from both realms of practice.
It was not until 633 that Heraclius's Monoenergism began to receive resistance from the Chaldeconians, primarily from the monks Sophronius of Jerusalem and Maximus the Confessor.
[29] The eventually forbade discussion on whether Christ had one or two energies within him and instead insisted that the Lord had two different natures incarnated within a single will and body.
This document defined Monothelitism as the official imperial form of Christianity, and it would remain very controversial in the next years after its implementation.
[35] Finally, following the death of Heraclius in 641, both the subsequent Emperors Constantine III and Constans II were of orthodox practice and appeared to have removed the Ecthesis as the official imperial doctrine, by request of Pope John IV.
[36] This effectively crushed the remaining foundation of Monothelitism doctrine as Orthodox teachings appeared to quickly restore back throughout the Empire.
The resulting Roman Easter synod of 680 concluded that Christ had two wills and that all who had opposed this belief were to be condemned as heretics.