Some people have a misconception regarding Astrology or Jyotish that it is the rays emanating from the planets that affect our lives or have some concern with our destiny but that is a myth. Rays can only produce some physical effect. Just like Sun rays produce heat & give away light. Similarly rays emanating from Moon on a Full-Moon day are responsible for producing tides in the sea. They have no concern with our destiny.
It is not the rays but the planetary positions at the time of a birth of a person as seen from his birth place which have some correlation with the person's personality as well as his destiny regarding various issues of his/her life. The theory given by some so called astrologers that if we wear gemstones related to some planets then the rays coming from those planets will penetrate those gemstones and will enter our skin and will alter our destiny is not correct. It has been observed that gemstones produce some effects on the state of mind or in some cases state of health of a person.