Eyjólfur Pétur Hafstein the author of The Therapy of Sound and Light and Living on the Right Frequency - A Course in Occultism, and the composer of  Beneficial Sounds for Body and Mind, Sound of Reunion and Sound of Creation, was born in Iceland in 1951. He is a scientist and has worked for several years on his research concerning sound and light and their effect on man. Hafstein has a holistic view on the human being and his interpretation on reality is based on that view.

Hafstein writes: During the summer of 1989 my mind expanded and I became aware of other sources of knowledge within myself. Explanations of certain questions I had been wondering about became clear, and this knowledge began to assume a definite form. To begin with, I received an accurate explanation of the base 7-number system and its position in relation to the base 10-number system and other number systems. Then followed an awareness of how light is refracted into the seven colors of the rainbow. It was made clear to me how the seven colors and the base 7-number system were connected, and that this constituted the mathematical basis of the inner planes. In fact, numbers as we know them were shown to be simply an expression of certain colors. I learned that it was possible to record all numbers in the form of colors, and that this would be introduced within a short time frame on the physical plane. It was revealed to me which number corresponded to which color, and this all seemed to make mathematical sense.

About one year later, a new element, music, was added to this teaching. It was made clear to me that the octave of the musical scale was in fact a sequence of seven tones, based on the base 7-number system. With seven tones within each octave, the number 7 was shown to be a fundamental element in the three-element system (numbers, colors and tones). I received information on how tones were related, both mutually and to the seven colors of the rainbow and the base 7-number system.

After this, it was pointed out that the knowledge I had been given was the key to creation itself, and that our higher self, or soul, as we so often call this part of ourselves, uses this system. As an example the soul creates its personality with this method when it takes on an incarnate form in order to acquire knowledge by experience. I was also shown how this knowledge can be used in creative work on the physical plane.

Having completed this part of the teaching, my soul made the following proposals to its personality: ''I am your creator, and I have determined every step you have taken, without you being aware of this. I have now undertaken a particular task for the higher powers involving work on the physical plane during the time I have you in an incarnate form. This work is aimed at demonstrating scientifically that I am real, and that all men have a higher self, or soul, which is as real as I am.

''I have decided to carry this out in a particular way, and you were created in accordance with this. All that you have done in life, as well as your education, has gone ahead with this aim, even though you have not realized this until now. Know that you can receive all my knowledge, but due to the limitations of the human brain, I am only able to give you a part of it. Well, work awaits us! What I intended to ask you was: Will you co-operate consciously with me on carrying out this task? I need your assistance. If you agree, it will simply mean that you will be aware of what course the project is going to take in the future. If you decline, it will not matter. I created you, and will still control you none the less. I shall carry out the task, though perhaps I will not acquire the experience I am seeking. If you agree, then more will happen besides your being able to see into the future. I shall give you my complete support and that of the group within which I operate, and consequently my creative powers, though naturally under my control and only for use in the tasks I accepted during this incarnation.

''What we need to do is divided into several parts, and the whole project will take a number of years. Firstly, you must demonstrate that the science of numbers is the science of color. Secondly, you must show that tones and colors in the order and interaction that I have taught you can heal the ills of the personality. Thirdly, and following from this, you must lay down the basis of medicine of the New Age by introducing the classification of diseases and composing music for healing. The fourth part of the task is to describe all this in writing.

''When you begin the work in earnest, you will realize that there is no personal life ahead of you. You will have to dedicate yourself completely to this task and deny every type of personal, selfish life-style. But do not worry, I shall look after you.''