The Lord said: “And again, he that receiveth the word of truth, doth he receive it by the Spirit of truth or some other way?” (D&C 50:19) Light comes from God, but it is delivered within you. It projects into your heart and mind from inside of you. You may have experienced this when you attended a sermon where ideas came to your heart and mind that were different than what the speaker was saying.
When we learn, it is not through receiving some external teaching, but through perceiving and receiving the reaction of the inner light to the external catalyst. “For behold, again I say unto you that if ye will enter in by the way, and receive the Holy Ghost, it will show unto you all things what ye should do.” (2 Nephi 32:5)
There is no reason that this gift should be limited to settings and topics that we regard as “religious,” as such boundaries are artificial. God makes no such distinction between religious and practical things:
34 Wherefore, verily I say unto you that all things unto me are spiritual, and not at any time have I given unto you a law which was temporal; neither any man, nor the children of men; neither Adam, your father, whom I created.
35 Behold, I gave unto him that he should be an agent unto himself; and I gave unto him commandment, but no temporal commandment gave I unto him, for my commandments are spiritual; they are not natural nor temporal, neither carnal nor sensual. (D&C 29)
While God uses messengers and experiences to teach his children, he never fully lets go of the reins. God never expects any of us to believe anything we hear from any source without an independent confirmation through that portion of his spirit that resides in us. We are responsible not for what others say, but how much diligence we exert in searching it out, and what obedience we render to the response of our internal light in response to what we experience. He will adapt everything we hear to what we are prepared to hear—giving us customized instructions upgraded or degraded from what is being preached to match our awareness and circumstances.
One implication of this truth is that we can receive new truth from anywhere at anytime.
There are religious traditional sources of light and truth: visits from heavenly beings, visions, voices, and the like. There are sources recognized by both religious and secular people: dreams, impressions, etc.
Perhaps the richest and most overlooked source of all is everyday life. The light from God inside of you can use anything in your daily life to trigger an increase in your awareness, but it won’t often happen against your will. When we are observant of the world around us, and spend ample time in reflective meditation, we open the doors for the Lord to teach us new truth. Seemingly normal experiences in nature, at work, or in our homes can trigger an opportunity to learn deep truth.
The Lord sometimes reveals truth in obvious ways in the moment we seek it. But he often, and perhaps mostly, shows us while we are not expecting it. Because he is gracious, God does not leave us wallowing in ignorance. He directly reveals things to you out of the blue, and he intentionally places people with more light and truth than you in your life. He could do this with fire and earthquakes and neon signs, but that would require him to exercise great judgment when it is ignored or turned away from. Because he is merciful, and because he knows we will fail much more often than succeed, God typically offers us further light and truth ever so gently.
An example of this is provided in the story of the brother of Jared. In this account, the brother of Jared is commanded to build barges to cross the ocean. Because the barges are sealed, he worries about how they will have light. He approaches the Lord with 16 molten balls he had made, small enough to hold all of them in his hands at once. He asks the Lord to touch these stones to make them glow. The Lord touches each one, and in the process the brother of Jared sees one of the Lord's fingers. This shocks the brother of Jared, because he didn't realize that the Lord had the form of a man, and because he understood that seeing the Lord was something that could destroy a man because of man's impurity. The Lord graciously provided a little bit of revelation by preemptively showing the brother of Jared his finger. The brother of Jared responded by asking for more. He asked the Lord to show himself.
Perhaps the most important part of the story is very subtle:
For he had said unto him in times before, that if he would believe in him that he could show unto him all things—it should be shown unto him; therefore the Lord could not withhold anything from him, for he knew that the Lord could show him all things. (Ether 3:26)
Apparently, at some point in the past, the Lord had told the brother of Jared that if he would believe in the Lord, the Lord could show him all things. We are not given the account of how or when this happened. I would not be surprised if it was a routine, uneventful story. Yet, this small gem inside of that exchange was sufficient leverage for the brother of Jared to obtain an in-the-flesh visit of the Lord Jesus Christ.
This is how the Lord usually offers us further light and truth: through slight, imperceptible exchanges that will fly right past us if we are not paying attention.
Nephi noticed and leveraged his father's prophetic dream to obtain a dream of his own. The brother of Jared leveraged the Lord's promise to show him anything to see the Lord. David leveraged the Lord's strength in helping him kill a bear and a lion to help him kill Goliath. The list goes on and on.
The bad news is that you likely miss many opportunities to acquire more light and truth on a daily basis. The good news is that God is gracious, and he will call these things to your remembrance at a later time when you are more willing to pay attention:
24 He that loveth me not keepeth not my sayings: and the word which ye hear is not mine, but the Father’s which sent me.
25 These things have I spoken unto you, being yet present with you.
26 But the Comforter, which is the Holy Ghost, whom the Father will send in my name, he shall teach you all things, and bring all things to your remembrance, whatsoever I have said unto you. (John 14)
But there is more bad news; another chance will probably not come quickly, and it will not save you from the consequences of your not having more truth.