Although I can't comment on the motives of your psych professor, I can say that the various forms of flame meditation are, to put it kindly, rather odd.
The simplest version uses a candle as an object to focus upon while practicing typical blank-the-mind eastern meditation techniques. The practitioner concentrates on their breathing and whenever they are distracted, they open the eyes and look at the candle again. It's primarily a relaxation exercise.
Next, there is such a thing called violet flame meditation which gets a little wackier. This is based on the belief that there is an invisible spiritual energy within a violet flame that can totally transform a person's life. This is part of the very New Age field of color healing where violet is believed to have the highest "frequency" as well as the power to transmute the negative karma we acquired through the ages into positive energy.
Violet flame meditation is more of a visualization exercise and is conducted by reciting an opening invocation: "In the name of God, in the name of the Christ who is in me, in the name of the Holy Spirit, I invoke the violet flame and I ask the angels of the violet flame to... [make your requests for yourself, your family, your friends, your city, your country, the planet, as you wish]"
The practitioner is to visualize their heart glowing and emitting light rays like a sun, then repeat mantras or decrees for at least 15 minutes which remaining focused on visualizing a violent flame surrounding themselves. People needing a healing of some kind are to visualize the violet flame flowing through their arteries and healing them.
The session ends by reciting the concluding prayer: "In the name of the Christ within me, I ask that the light from these mantras and decrees be sealed in the physical plane and multiplied as cosmic law will allow, and I accept it done here and now according to the will of God. Amen."
Although these prayers refer to the God within, they are not referring to the Christian understanding of the God within - which is that God inhabits the souls of the baptized via grace. Rather, violet flame meditation refers to the New Age understanding of the indwelling God, which is that all of us have the divine within us and need only to find ways to claim that divinity and thus become the god we were always meant to be.
Another version of flame meditation is known as Tratak which involves meditating on a candle flame with the belief that the light emitted from the flame is caught in the lens of the eye which conducts the light and energy through the optical nerves to the lobes at the rear of the brain. This serves to increase the energy in the Pineal gland, also known as the Third Eye (a mystical and esoterical concept that posits this as a kind of gateway to higher consciousness and psychic ability) and improves its function. Practitioners claim the Hindu scriptures say the practice of Tratak develops greater intuition into the past, present and future.
Practicing Tratak is similar to other forms of flame meditation in that a person focuses on the flame for as long as possible without blinking. When one has to close the eyes, they should focus on the after-effect of the flame glow behind their closed eyes and notice how it changes size and/or color. When it disappears, they are to open the eyes and start the process all over. Whenever thoughts arise, they are to be pushed away and the concentration returned to the flame. This practice allegedly produces feelings of deep peace and relaxation and will eventually bring about a deeper knowledge of the Self, all leading to the path to Enlightenment.
As you can see by these three examples, the practice of flame meditation is not a Christian concept because the goal is to deepen knowledge of oneself rather than of God.
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