Today, February 6th, we commemorate the one whom some historians say was second to St. John Chrysostom in influence on the Constantinoplitan throne. I’ve decided to complete a blog entry about St. Photius because his teachings and the heresies he faced are as relevant today as they were some 1,200 years ago.
St. Photius ascended the Partriarchal throne after his predecessor, Ignatius, was deposed in the year 857. He was raised from layman to Patriarch in six days, which is unusual. He was a man of great learning in both secular and theological studies.
A great deal of controversy surrounded his quick appointment, particularly in the West. Pope Nicholas I sent delegates to investigate the matter and was assured that Photius’ appointment was legitimate. Years later, Nicholas changed his mind and held a council to anathematize Photius. Nicholas’ successor, Pope John VIII, later annulled the decisions against Photius and even sent him an omophorion (or pallium) to confirm Photius’ appointment. Many years later, the Latin (Roman Catholic) church reversed their decision again and they now support Pope Nicholas, whom they call St. Nicholas the Great.
A strict upholder of the faith, St. Photius wrote against a growing practice in the Latin West of the insertion of the filioque into the Creed, stating that it distorted the harmony of the truth regarding the Trinity. Because it was not widespread, he did not condemn the Western church as a whole, just those bishops who had changed the Creed.
We see in St. Photius’ rival, Pope Nicholas, the evolution of thought in the West regarding the Roman See (bear in mind this is 200 years before the Great East-West Schism). Nicholas sought to establish himself and all popes of Rome as the head of every Christian in the world. He hoped Photius would submit to papal rule, but when Photius would not, Nicholas became his enemy.
The life of St. Photius is filled with much political drama, and it would take a book to properly review it all. He stood firmly on the truth and traditions of the Church Fathers, and because of that, faced persecution from those who desired power more than truth (Pope Nicholas and various Byzantine emperors). His own father, Sergius, was killed by the iconoclasts, so persecution was nothing new to this brave soul.
St. Photius opposed papal claims to universal jurisdiction, the altering of the Creed with the filioque, iconoclasm, universal salvation as found in the corrupted manuscripts of St. Gregory of Nyssa, and other heresies. At the Eighth Ecumenical Council (in which delegates from Pople John VIII were present),
St Photius was acknowledged as the lawful archpastor of the Church of Constantinople. Pope John VIII, who knew Photius personally, declared through his envoys that the former papal decisions about Photius were annulled. The council acknowledged the unalterable character of the Nicean-Constantinople Creed, rejecting the Latin distortion (“filioque”), and acknowledging the independence and equality of both thrones and both churches (Western and Eastern). The council decided to abolish Latin usages and rituals in the Bulgarian church introduced by the Roman clergy, who ended their activities there. 
Several of the written works of St. Photius the Great have survived to today, though only a couple have been translated into English. The most complete work is his Mystagogy of the Holy Spirit.
Also, his Bibliotheca can be read here and here. It is a list of books which he read, summarizing the teachings of the fathers and sometimes quoting from them at length. It is a valuable source to historians because many of the books from which he quotes have been lost over time.
One noteworthy entry from the Bibliotheca regards St. Gregory of Nyssa. In it, he reveals that other saints of the church considered teachings regarding universal salvation to be corruptions in St. Gregory’s work. He says,
[I] read a book which has the name of St. Germanus… Bishop of Constantinople….”
The subject that defines this book, which is a polemical work, is to demonstrate that St. Gregory of Nyssa and his writings are free of any taint of Origenism. In fact those to whom this silly idea of the redemption of demons and men freed from everlasting punishment is dear are those, I say,…who have attempted to mix into his works, full of the light of salvation, informed, troubled and disastrous ideas from the dreams of Origen as part of the design to soil with heresy by a method which overturns the virtue and distinguished wisdom of the great man.
This is why, sometimes by faked additions, sometimes by their relentless efforts to pervert correct thinking, they have attempted to falsify many of his works which were beyond reproach. It is against these that Germanus, the defender of the true faith, has directed the sword sharpened with truth and leaving his enemies mortally wounded, he makes the victory apparent and his mastery over the legion of heretics who created these pitfalls.