Religion, as with any form of inquiry, ought to be based upon facts. While that statement may to some seem contradictory, it is nonetheless true. In order to be credible any pursuit should be built on a foundation of truth with an ordered evidential line to grant credence to it. Without order you can call something religion or worship, but it moves less through the lines of faith and more on emotion or simply upon the winds of acceptance and the strength of self-will.
As has been noted by others, facts are not subject to disappear when challenged. They are immutable. They are as fundamental and reliable as physical law. And without the recognition of laws and the accumulated record of the events, no religion, no establishment of nations, no civilization, no constitution, and no principle of human organization could long survive.
Here are some immutable facts. You will not find an answer to any inquiry as to how to save your soul in the writings of Zoroaster. Such things are not found there, and so no answer is given as the question was never posed in those ancient religious writings. This question does not occur in the writings of Buddha, or in the myriad text of the Hindu faith. Saving a soul doesn’t play a part in any of those writings and is not the basis of those religions.
You will not find the question: “What must I do to be saved?” in the Quran, look though you may. And if you do not find the question, you will then also not find the answer.
But, you will find this question asked repeatedly and answered quickly within the New Testament. And only there will you find a clear and simple answer to it. It was not asked only once, but on several occasions. And the question and its answer are found in the Book of The Acts of The Apostles. You will also find the question and its answer discussed repeatedly within the pages of the several letters of Paul, and in details within the other writings of the New Testament.
Do you suppose that is a coincidence?
Then I said, Lord, what should I do?
And the Lord told me, “Get up and go into the Damascus, and there you will be told about everything that is assigned for you to do.”
Since I couldn’t see because of the brightness of that light, I was led by the hand by those who were with me, and came into Damascus. Someone named Ananias, a devout man according to the Law, having a good reputation with all the Jews residing there, came to me, stood by me, and said, “Brother Saul, regain your sight.” And in that very hour I looked up and saw him. Then he said, “The God of our fathers has appointed you to know his will, to see the righteous one, and to hear the sound of his voice. For you will be a witness for him to all people of what you have seen and heard. And now, why delay? Get up and be baptized, and wash away your sins by calling on his name.”
(Acts 22: 10 – 16)