Not a lot is known about who the Holy Ghost (Holy Spirit) is, but we do have a good idea as to how he works, and about his nature. Of the three people in the Godhead, the Spirit is the only one who does not have a physical body. He is a personage of spirit. There is something about him still being a spirit that allows him to do what the other two cannot do. If they could, then there would be no need for him. His responsibility is to testify of Christ and the Father and of the truthfulness of all that they teach.
The Spirit is our personal tutor. His assignment as a member of the Godhead is to testify of truth wherever it is found. He uses the light of Christ, which has been given to all of humanity as our conscience, to teach us right from wrong. As we listen to our conscience (the light of Christ), the Holy Ghost gently leads us to greater truths and greater enlightenment. The goal is to bring us to the Gospel of Christ. Once exposed to those truths, he witnesses to our souls the truthfulness of what we have just learned. But he doesn’t do so by just telling our brains, his communication is spirit talking directly to spirit. The nature of his witnesses are permanently imprinted into the fabric of our souls so they cannot be denied without severe penalty from the Father. We have been told through the prophets that even if Christ himself were to show himself to a person, if that person betrayed Christ’s witness he could still be forgiven for it. But if that person is given an absolute witness of Christ through the Holy Spirit, with or without seeing Christ, and that person betrays that witness, then there is no forgiveness to be had. That witness is absolute and binding in the courts of heaven.
All revelation is had through the Holy Ghost. All understanding of eternal principles are had through the Holy Ghost. I have seen with my own eyes what happens to someone who has been blessed by witness from the Holy Ghost, who turns from that knowledge and chooses to follow other paths. They lose their ability to comprehend what they once knew so intimately. Where once they had the ability to understand things with an eternal perspective, now they can’t see past the end of their own nose; even the simplest of truths is beyond their grasp. It is frightening to see it happen, but going the other direction, it is exciting to see someone who has little comprehension of eternal things suddenly start to see how things fit together and to be able to understand things more and more like God wants us to understand things. They really do have their eyes opened. This is the work of the Holy Ghost, to lead us to God.
In the scriptures we are taught that when we study the word of God and pray for understanding and for a knowledge of the truthfulness of what we have read, that the Holy Ghost will reveal it to us. We are told that we will have a burning in our bosom if it is right. If it is not right then we will have a stupor of thought that will cause us to forget the thing we asked for. How people describe the burning of the bosom is different for each person. Some will tell you that they feel a lightness of being that brings great joy. Others will tell you that their whole chest will become warm, and a comfort will settle around them like a warm blanket on a cold night. Still others will say that they experience a thrill of understanding and knowledge that fills their soul with gratitude for the new knowledge gained. There are many ways for the Spirit to speak to us, and he will do it in the way that will best suit our needs at the moment. Suffice it to say that the witness does come when asked in sincerity and when the requisite studying and faith have been demonstrated.
This brings up an important point. God really does want us to have knowledge of him. Yes, there is still faith, there is always plenty of opportunity to exercise faith, but God does not want us to wander through life in ignorance with only faith to rely upon. God wants us to seek after knowledge so that we can become more like him. That is, after all, the purpose of our being here in the first place. And what better way for us to be able to make wise and eternally important choices than to have the knowledge we need to make those choices correctly? Faith is just supposed to be the precursor to knowledge. Each time we change faith into knowledge we have the opportunity to exercise faith in something higher and more difficult. Step by step we grow and become more like Christ. This is why the Lord says we cannot be saved in ignorance. He expects us to seek Him out and learn His ways. Christ expects us to become like Him. We do this through the help and instructions we receive from the Holy Ghost.
Click on the title of the video to see the talk by
Marion G. Romney on The Holy Ghost