We follow the Moon Calendar whereas the foreigners follow the sun calendar. This is the reason that the dates of their festivals never get changed. But all our festival depends on the Moon. That is why the dates keep changing and all our festivals are celebrated on different dates.
We give much significance to Moon and decide all our dates and festivals according to it. The reason being the effect of the Moon on human being is much more than of the Sun. Other planets also have their effects on human beings. So we go according to the Moon and fix the dates of the festivals.
Only one of our festivals is fixed by the position of the Sun- the day, when the journey of the Sun starts towards Equator (Uttarayana). On that fix day we celebrate one of our festivals – Makar Sankranti.
Throughout the country this festival is celebrated on the same day. This date never changes. All our astrology and astronomy go with the position of the Moon. The state of the Moon is considered in astrology and astronomy and the whole astrology is made accordingly. So our first calendar Shalivahana Shaka is based on Moon. All the dates also go according to Moon. Those who have no knowledge of these facts can not understand the reason behind this festivals falling on different dates. So we have to think that the significance we have attached to the Moon is because it has a great impact on the human beings. We should be careful about it.
The greatest effect of the Moon is that our left side (Left Sympathetic) depends on it. Very few people know about it. The reason of giving so much importance to this left side is that it affects our psyche. That is why so much significance is attached to it. The effect on the left side is psychic; it does not belong to our brain. It can not be controlled.
Psychic problems can not be controlled nor the effect of the Moon. So the dates of the Moon are to be considered. For example on Amavashya (New Moon Night/No-Moon night) or Purnima (Full Moon night) the problems of epileptic or psychic patients gets aggravated. On such occasion we could see that the person is affected by No-Moon (Amavashya) or Full Moon (Purnima). So we are sensitive to the position of the Moon. Very subtle calculations have been done about it. In our country we know much before the dates and times of Moon eclipses. Much thought have been given to it and we have acquired a lot of knowledge about it. It shows that a lot of attention has been given to the effects of the Moon. So much has been written about it.
H.H.Shri Mataji Nirmala Devi, Gudi Padwa Puja, Gurgaon, India, 13/4/2002