Paul taught:
13 For whosoever shall call upon the name of the Lord shall be saved.
14 How then shall they call on him in whom they have not believed? and how shall they believe in him of whom they have not heard? and how shall they hear without a preacher?
15 And how shall they preach, except they be sent? as it is written, How beautiful are the feet of them that preach the gospel of peace, and bring glad tidings of good things!
16 But they have not all obeyed the gospel. For Esaias saith, Lord, who hath believed our report?
17 So then faith cometh by hearing, and hearing by the word of God. (Romans 10)
In this passage, Paul highlights that while God is the source of truth, because of our limited awareness, we typically require a third party to help catalyze our recognition of further light and truth.
All truth comes from God. While it is more commonly the case that the light inside of us teaches us in response to the teaching of others, we can also obtain light and truth directly from him.
An analogy will help illustrate the relationship between finding truth directly from God and finding truth with the help of another person. When you look at the sun with your naked eye, you see an orb of light so intense that you can’t make out an exact shape or any details. You can’t look for very long because of the pain it induces. Because you can’t stare at the sun, you have to sense it indirectly: through ambient light, through heat that you feel on your skin, and through its effects on other objects. The sun actually has a tremendous amount of detail to it. We can't see it with our eyes because there is so much light flowing from it that it overloads our sight. In order to see it, you have to filter out a great deal of the light coming from it. Light bearers act like a wavelength filter through which we can see previously unbearable details of the sun. It is not a complete picture, but it is a marked advancement over what we previously had.
God's light and truth flows in and through all things, even those things that do not recognize him. The light shines at full blast, but we don’t comprehend or perceive it. What lies outside of our awareness is necessarily unknown to us. Those who have a greater awareness can help us obtain the same in ways that are much faster and forgiving than our direct attempts. The role of light bearers is to reduce God’s glory to something much easier to digest—a small chunk—and distribute it to the masses, in hopes that they can develop the capacity to recognize, comprehend, and endure God's glory directly.
While obtaining light directly from God is ideal, it is also the most difficult way. There are two benefits to obtaining truth from others. First, it is faster. Second, it is more forgiving.
The intercession of others makes truth available to you beyond what your own heed and diligence merits. God went through a lot of effort to make sure that there were noble and great ones sent to earth in order to make truth available beyond what an individual could get on their own (see, for example, Alma 13). An analogy is found in the relationship between established trees and new trees. The new trees have shallow roots, and the rain ensures that nutrients are washed deep into the soil. The established trees help the new trees grow to their stature by pulling the deep nutrients up from the earth and distributing them on the topsoil through shedding their leaves. This is how those with greater light and truth make these things available to those with less light and truth. People who possess more light and truth than most are rare but can provide access to light and truth that would take most people many lifetimes to acquire.
The pattern throughout scripture is that a human obtains light and truth, then shares it with others. For example, the apostle John taught others what he had learned from the Lord directly, giving a reason for them to believe it could be true: “We know this is true, because it was told by someone who saw it happen. Now you can have faith too.” (John 19:35, CEV)
The Lord uses those with greater light to help those with less light, because without them, those with less light would not have the means to obtain sufficient information to progress:
And by so doing, the Lord God prepareth the way that the residue of men may have faith in Christ, that the Holy Ghost may have place in their hearts, according to the power thereof; and after this manner bringeth to pass the Father, the covenants which he hath made unto the children of men. (Moroni 7:32)
Every step along our truth progression is like a ladder. The rungs of the ladder are composed of ever-increasing light. Some of these rungs come through people who possess the light we lack. You never know if the people you meet every day might be the source of the next packet of light in your progression. When you come across someone who might have more light, you investigate what they do and why they do it. You sift through what they have to offer, and test the things that pass the bar of what might be true. You assimilate what passes your tests, and then you move on. Every time you have sifted through a person’s light, and applied all they have to offer, you can return to God and say, “Lord, I have been true and faithful to everything you have given me. Give me further light and knowledge.” Then, he will send you someone else.
As a truth seeker, you are like a gold miner. You might discover a very rich seam of gold on your own in a virgin landscape. Odds are that you will not be as successful as those who have gone before you and have discovered, mined, and sorted tons of gold. The difference between light and gold is that light does not diminish with sharing. Imagine two people mining gold. They can’t share their gold without giving it away. Light and truth is also mined, but sharing it does not diminish it. Now, imagine one person, through their prolonged obedience to God and well-developed desire, has the equivalent of modern machinery in their mining operation, while you have the equivalent of a pick axe.
By paying attention to the light and truth obtained by that other person, you can gain all the benefits of having built up a modern operation without having expended any of the time and capital they required to get there. By perceiving the light in others, you can launch ahead in light and truth far beyond what you could on your own in the same amount of time. By finding human sources of light, one can acquire, evaluate, and integrate several lifetime's worth of light in much less than a lifetime.
Here we must make a note to say that salvation is not as easy as finding and mining light bearers. While the existence of those with greater light and truth is a tremendous blessing, it is a situation that must be navigated with care. It is rare that anyone interacts appropriately with this resource. When it comes to obtaining light and truth through others, we tend to do one of two things: we either set this person up as a guru, or we reject them out of hand.
Your objective is not to fixate on them, but to investigate and test their model. Acquire what is valid, and find the cracks in what is not. Eventually, you will rise to their level, and if you continue to hunger and thirst after more truth, you will overtake them, as the quantity of light that you obtain is determined by your “heed and diligence,” or effort in acquiring and assimilating it.
What does it mean to surpass them? You will have answers to questions they do not know the answers to, and you will have stronger answers than they do (answers that stand up to stronger criticism). These people are like landmarks. On a flat plane, you can only see so far. But you can see landmarks closer to you that you imagine are in line with your ultimate goal. As you walk towards those landmarks, you might be able to figure a more accurate bearing to your ultimate goal.
Light bearers are all around you to a greater extent than any other time in the history of the world thanks to modern technology. The internet gives us access to the entire population of holy men on the earth just as soon as we are ready to search for and hear them. What are you doing with this advantage? Are you screening more putative truth and obtaining more tested truth than prior generations? How much time and effort do you spend reading books and watching videos from great (whether popular or not) minds, testing their principles against what the Spirit tells you? Remember that when much is given, much is expected. You should ask yourself why God has made it easier for our generation than any previous generation to obtain more light, and ask what he expects you to do with it.