There are three major elements about the light to comprehend. First, what the light is, second, what the source of the light is, and third how you can experience the light.
The essential goal of all religions is to have their devotees become enlightened. Jesus was an enlightened man. The Greek word for light means light as seen by the eye, or expressly to shine or make manifest by rays. Jesus was a man who came into this world to give light. To understand Jesus and his teachings it is necessary to understand Light and its' source. The mystery which Jesus taught his disciples is that the light he was one with was not a metaphor but was real light.
In the Gospel of St. John Jesus stated, "I am the light of the world; the one following me by no means will walk in the darkness, but will have the light of life." This is the essence of the mystery which Jesus taught. Not only did Jesus receive and then become the light, but he taught those who follow him will also receive and become the light. To experience the light means to see it. The experience of seeing the light is called the illumination. To have this experience it is necessary to take the journey within.
Going within oneself is the art of focusing your consciousness in and upon itself. While in a thoughtful state examine the phenomenon of your mind itself. You will discover that it seems to exist mainly in the forehead region of your head, and just behind the eyes. As you examine this placement of your mind you will also discover the feeling that your mind sees through your eyes.
If you can think back to a time when you may have had a sudden inspiration or an intuitive flash, think about the source of the inspiration. You will discover that the inspiration or intuitive flash actually came from a much deeper space within you. If you concentrate on the space that the intuitive flash came from you will discover it came from the space behind your solar plexus. This is the space which is being described as within.
In the Gospel of St. Luke the Pharisees are questioning Jesus about the kingdom of heaven and Jesus says, "Comes not the kingdom of God with observation, nor will they say: Behold, here or: there behold for the kingdom of God within you is." The Greek word for within used in this passage is entos, which means inside. Therefore Jesus was saying to get to the kingdom of heaven you must go inside of yourself.
The experience of the light is mentioned in both the Bible and the Gnostic Scriptures. In the Acts of the Apostles, Paul's experience of seeing this light is described as, "In Now the to go it came to pass him to draw near to Damascus, and suddenly him shone round a light out of heaven." In the Greek text this light is referred to as light out of heaven.
The light which Paul saw came out from inside of him. This light was so profound that Paul was blinded for three days. We can know that the light which is being talked about in this account is actually light and not a metaphor by two facts. The first fact is that in the original text the Greek word which means light as seen by the eye was used, and second because only real light can cause a person to go blind.
In the Gnostic Scriptures we will find even more revealing references to light. In the Gospel of Matthew, Chapter 22 verses one through eleven there is a parable about a king who invited guests to a wedding. When one of the guests showed up without his wedding garment, he was thrown out. This parable is about the marriage of man's lower nature to the Christos. We find explicit reference to the wedding garment in the Gospel of Thomas, "The forces do not see those who have put on the perfect light and cannot seize them. One will put on the light in a mystery, through the act of joining." Thus the garment that we all must don is the garment of light.
The greatest mystery is the source of the light. The source of light is the Christos. In the Gospel of John we also find the Christos being called the word (logos), which means the personal manifestation not of a part of the divine nature, but the whole Deity, or image.
The Christos is the only begotten of God. The Christos is "the uncontaminated light." It is this uncontaminated light which is the anointed. "And the spirit anointed it (the Spark) with its own kindness until it became perfect, needing no further kindness since it had been anointed with the kindness of the invisible spirit." Christos means the anointed.
The Christos is also associated with the Word. Both the Gospel According to St. John and the Secret Book According to John declare that all things were made by the word. In the Gospel it states, "In the beginning was the Word, and the Word was with God, and God was the Word. This one was in the beginning with God. All things through him became, and without him became not one thing which has become."
The mystical union of the Christos and Jesus is one of the great spiritual mysteries. To get a rudimentary understanding of this union it is necessary to use an analogy. If you picture the Christos as an ocean and Jesus as a drop of water which has been dropped into the center of this ocean (Christos), then you have a way to understand this union. While the drop of water (Jesus) did not cease to be, it did become indistinguishable from the ocean (Christos).