Saint Theodore the Studite writes some things that are very good to remember. We behold the Protestants and other zealous and very well-intentioned heterodox racing all over the world translating the New Testament for everyone to read, bringing medical supplies, building schools and orphanages, and doing many good works of mercy. All very laudable, and I have little doubt that there is a huge amount of genuine love and compassion for humanity there, and also a real solid, natural desire to please the Holy Trinity there. However, St Theodore warns us with the Voice of the Spirit of Truth, that such works do not SAVE us if we are heretics, or in communion with those heretics. It sounds barbaric to our modern sensibilities, but this is simply the case. We MUST be ORTHODOX if we would be saved. Doctrine really does matter, no matter what popular opinion is today--even among traditionally minded and "Bible-defending" Christians. Deviant, unOrthodox doctrines make us ENEMIES of Christ, no matter how sincere and energetic our efforts to be True Christians are. Period.
“Even if one should give away all his possessions in the world, and yet be in communion with heresy, he cannot be a friend of God, but is rather an enemy.”
St. Theodore the Studite
(PG 99, 1205)
“Chrysostomos loudly declares not only heretics, but also those who have communion with them, to be enemies of God.”
St. Theodore the Studite
[ Epistle to Abbot Theophilus ]
“Guard yourselves from soul-destroying heresy, communion with which is alienation from Christ.”
St. Theodore the Studite
[P.G. 99.1216.]
“The heretics were totally shipwrecked with regard to the Faith; but as for the others, even if in their thinking they did not founder, nevertheless, because of their communion with heresy they are perishing.”
St. Theodore the Studite
[Patrologia Graeca 99, 1164]