Q. Which Lutheran denomination retains the proper doctrine?I'm going to ask (yes, in the face of the Catholic-Orthodox split) why there would be multiple Lutheran churches with the same "original Tradition of the church". What is it which divides them into multiple churches then? Issues not pertaining to salvation, if I read you correctly. But if that is the case, why must they divide? Why cannot they remain united as one church abiding by that famed motto of the Reformation coined by German Lutheran theologian Peter Meiderlin (or Rupertus Meldenius), "in necesariis Unitatem, in non-necessariis Libertatem, in utrisque Charitatem"? AND are there any non-Lutheran churches which possess this same "original Tradition of the church"? If there are, why are they separate from the Lutheran church(es)? If there are not, then are there churches that contain enough of the "original Tradition" to still have hope for salvation?
A. The one(s) still holding to the original Tradition of the church, that handed down by Christ through the apostles.
Q. What is necessary for salvation?
A. Christ is necessary for salvation. Doctrine, in its best sense, is a full life-giving knowledge of God and his kingdom. Unfortunately, "doctrine" often becomes a set of propositions to be memorized whose content (in theory) could convey some knowledge of God and his kingdom if only people weren't so busy mistaking doctrine for salvation. It would be like mistaking the nutrition label on the can for a nourishing meal. (See, it says right there, "100% iron, 100% calcium ... and I already read the label so I'm set! I read it twice, so I'm more nourished than you!") What Christ said about Scriptures could easily be said about doctrine: You eagerly search them because you think that by them you have eternal life. These are they that testify about me, yet you refuse to come to me and have life.
There are all kinds of things that are true (Lutheran doctrines, Roman Catholic doctrines, doctrines of all kinds of other groups too numerous to name) that are not "necessary for salvation". There are things that are true about God, but knowing them is not "necessary for salvation". If doctrine isn't necessary for salvation, then what is the purpose of doctrine? To bless us through knowledge of the Holy One. I have often asked myself, "Is there really any other blessing besides God?" To know God is to have peace and patience and perseverance. To know God is to have the fullness of love. To know God is to have complete freedom from fear. To know God is to have all wisdom. To know God is to be joyful. What good thing is outside of him? That is what doctrine is about: there is no higher blessing than God.
I certainly agree that "Christ is necessary for salvation" and that through doctrines we are "bless[ed] through knowledge of the Holy One", who is God in Three Persons, one of Whom is Jesus Christ. But the Word is a living Word, and as such I also agree that mere knowledge of these doctrines will not suffice, any more than living among ten thousand Bibles will bring you salvation. These doctrines are to be known and lived by. As a Catholic, I don't hope to be saved because I believe Mary was assumed body and soul into heaven, but I have hope of my own salvation (and resurrection) because of what has been revealed about Mary. Likewise, I don't hope to be saved because I believe the bread and wine are transubstantiated into the Body, Blood, Soul, and Divinity of Jesus Christ, but I have hope for the continuing strength and perseverance in my life of faith because I am nourished by that same Eucharist I believe in.