Hindus follow 7 days week & 15 days lunar cycle

The 7 day week is not really based on western calendar. Firstly, lets look at how classic Jyotish Shastra of the Vedas answers to these questions: Why do we have only 7 days in a week? Why can't we have 8 or 9? What is an hour? Why do we have only 24 hours in a day? Why can't we have 30 or 40 units and call it an hour? Ancient Indians were so well versed that they often used 4 to 5 different units of time. If you ask your Indian grand mother, she might have told you that during her days, people measured time in a weird unit called ghati/ghadiya (1 ghati = 24 minutes).

1 day is the time lapsed between two sunrises. Sandhi in Sanskrit means knot or junction and hence the junction points are named as pratah sandhya and sayam sandhya which divide the standard day into two halves i.e from sunrise to sunset and sunset to the next sunrise. Since there are 12 zodiac constellations, each constellation is assigned a part of the half a day unit and hence 12 parts in half a day each, together 12+12 = 24 units. This is the concept of hora. (Yes, hora is the standard hour. English unit of time and Sanskrit unit of time named similarly. Strange coincidence, don't you think so?) Just as there are constellations associated with each hora, each graha is assigned rulership of individual hora. The order of the planetary rulership of horas is as follows.

1) Surya (Sun) followed by

2) Shukra (Venus) followed by

3) Budh (Mercury) followed by

4) Soma (Moon) followed by

5) Shani (Saturn) followed by

6) Guru (Jupiter) followed by

7) Mangal (Mars).

In jyotish shastra, the rising sign at the time of sunrise is noted down and is considered very important to make any astronomical/astrological calculations regarding a chart, esp. to find out the janma lagna, it is is very essential. So, the rising sign is very important. Likewise, the planetary rulership of the hora during the time of sunrise is noted down. The planet that rules the hora at the time of sun rise is assigned the rulership of the whole day. And hence,

The day Ravi-var (or Sun-day) is named after Ravi/Sun who is assigned lordship of the day because he rules the hora at the time of sunrise of that day. Now, following Sun, the next hour after sunrise is ruled by Shukra followed by the rest. In the above mentioned order of rulership of horas, calculate the next ruling planet that comes after 24 horas, i.e

1st hour by Ravi, 2nd hour by Shukra, 3rd hour by Budh,

4th hour by Soma, 5th hour by Shani, 6th hour by Guru,

7th hour by Mangal,

8th hour by Ravi, 9th hour by Shukra, 10th hour by Budh,

11th hour by Soma, 12th hour by Shani, 13th hour by Guru,

14th hour by Mangal,

15th hour by Ravi, 16th hour by Shukra, 17th hour by Budh,

18th hour by Soma, 19th hour by Shani, 20th hour by Guru,

21st hour by Mangal,

22nd hour by Ravi, 23rd hour by Shukra, 24th hour by Budh

25th hour by Soma

As you see it turns out that Soma is the ruler of the next day's sun rise. And hence, the next day Soma-var (or Mon-day) is named after Chandra/Moon who is assigned lordship of the day because he rules the hora at the time of that day's sunrise. In the same order, Mangal-var (Tuesday) for Mangal/Mars being the hora ruler at sunrise, Budh-var (Wednesday) for Budha/Mercury being the hora ruler at sunrise, Guru-var (Thursday) for Deva Guru Brihaspathi/Jupiter being the hora ruler at sunrise, Shukra-var (Friday) for Shukra/Venus being the hora ruler at sunrise, Shani-var (Satur-day) for Shani/Saturn being the hora ruler at sunrise, Now after Saturday, the cycle reverts to 1) with Surya being the ruler of the hora at the time of next day's sunrise. This is the reason why there are only 7 days in a week based on these calculations of hora and their planetary rulership as mentioned in the vedic texts.

One may be a Christian, Muslim, Sikh or Jew, knowingly or unknowingly they follow the methods of the ancient Indian rishis. This is the reason why Hindu dharma is called Sanatana dharma (i.e eternal and expansive in its very nature). It is funny how the whole world believes that the 7 day week is a western concept! The Horas etc. But, would like to add how it is related to human body, the Lunar cycle, 12 month, 24 hrs connection.

I will touch upon just the surface.Real details are available in Patanjal Yogasutram, Hatayoga-Pradipika, Bramhavaivartapurana, Tamil Thirumanthiram, Shrimadbhagavadpurana and above all the human biological cycles you already know. Some people can observe subtle & distinct cycles in body everyday in 24 hrs if they do Nadishodhan and some Pranayama practices as per my own experience.

Why there are 12 months & Lunar cycle? It is for the same reason that you have 12 Major Music Scales-chords and 12 Minor scales- chords in Music equivalent of Raagas (total 24). In music you have 7 white keys and 5 black keys making them 12 in Piano, Harmonium and same sharp, flat concept exists in Guitar. There too you have definite Harmonics calculation that is recognised by every human Body. If 1st key of piano is 400 Hz, then 2nd key is 400 X 2 ^(2/12)=449 Hz and the 12th is 400 x 2^(12/12)=800Hz. So, Music has zodiac dependence as appreciated by human brain. The same is true about number of colours that is appreciated by brain (7--ROYGBIV--Red, Orange, Yellow, Green, Blue, Indigo, Violet).

Please follow the details:-1. Female Biological cycle-Menstrual cycle is based on Lunar and it repeats about 12 times in a year periodically.A perfectly healthy body would repeat cycle exactly on the same Tithi (lunar day-lunar position w.r.t that lady)

2. Hence, the whole sphere around earth or rather a person (Jyotish term-Jatak- english term-subject) is divided in 12 Zodiacs and hence 12 months.

3.Every person on earth travels through 12 zodiacs everyday with earth rotation.

4.Every Zodiac has Lunar half and solar Half in laymen language.Hence there are 24 parts of the spatial arrangement around everybody throughout the day.

5. In everyday travel from one part to other, Airflow of breathing changes nostrils-swara 24 times in day from Left to Right or vice-versa & other nostril getting partially closed.That is why we have two nostrils.The left-Lunar nostril when blowing full-open, it cause all cooling mechanisms of body and if remains open unchanged continuously for 20days, person will die of cold diseases such as Pneumonia. A CT scan showing below evidence of the nasal cycle. The more patent airway is on the right; the swollen turbinates congesting the left. 7.Detailed 15 day Nostril Changeover chart is reproduced below which tells you why 15day lunar cycle? The Right nostril-solar Nostril when blowing full-open, it activates all the heating mechanisms of the body such as metabolism.20 days principle is applicable for this too and in this case person dies of heat related diseases such as Heat stroke etc. (Ref-Patanjali Yogasutram). So, every alternate hour (60 minutes), body changes from heating to cooling or vice versa carrying out all body functions and maintaining body temperature.This is called Intermittent Split Range system of control in Industrial Engineering Process control

As there are only 9 Grahas which actually affect-control human biological cycles, Jyotish needed only zero & additional nine digits (0,1,2,3,4,5,6,7,8,9) devising the Decimal numeral system to model the whole Jyotish. You all know decimal Number system is the one that is exhaustively used globally.

This is very brief just to tell you why there are 24hrs in a day, 7 days in week, 12 months in an year. Other details why there are 60 minutes in an hr, 24 minutes in a Ghatika, 60 Ghatikas in a Day, 8 Prahars in a Day ? Its interesting as everything is related to positions of 9 planets around human body at any time ( I would say Grahas as Planets definition is not equivalent to Grahas of Jyotish-Grahas includes the planets: Mars, Mercury, Jupiter, Venus, and Saturn, the Sun, the Moon, as well as positions in the sky, Rahu (north or ascending lunar node) and Ketu (south or descending lunar node), Weekdays are there for Mars, Mercury, Jupiter, Venus, and Saturn, the Sun, the Moon except Rahu & Ketu as they are fictitious positions w.r.t sun and moon positions). The Pranayam system of Yoga takes advantage of all this information to carry out the tuning of human body as per Jyotish and remain fit. Jyotish and Yoga are complementary. The mythology of Puranas in details discuss all these vital information with exact data.

Simultaneous involvement of different cycles improves the time-keeping process and also what we make out of time. Since astrology was back then some sort of astro-psychology . Each cycle was given its due importance. Movement of the sun (i.e. in fact Earth) affects us most, or we can say that the effect is seen very easily. Effect of Moon can't be easily felt when compared to sun, but it is still quite visible in form of tides. When we talk about planets, effect occurs in the inner realm, additive, drop by drop, inch by inch. For example we have Barhaspatya cycle of 60 years, it goes exactly like the Chinese zodiac. Each year having a specific name and each year repeats itself after 12 years. 12 years is in fact a Jovian cycle. Bigger cycles like the one of the changing pole star are also mentioned ( we current live in Laukika era, when pole star lies close to Ursa Major ). These cycles don't affect individuals, as the time span involved is just too much. These cycles affect mankind as a whole. Such cycles govern paradigmatic changes that happen throughout the course of history. Jay Shri Gurudev

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