Shakat Yoga is considered as a malefic yoga in Vedic astrology. According to its prevalent definition; if in a horoscope, Moon and Jupiter are placed in 6th and 8th houses with respect to each other, Shakat Yoga is formed in such horoscope. This yoga can trouble the native with problems related to finances, wealth, profession, health and many other things.
In real practice, Shakat Yoga is not seen producing such results when only the aforementioned condition is met. Hence more conditions should be met in order for this yoga to be formed effectively in a horoscope. Both Jupiter and Moon should be functionally malefic in such horoscope. If one of them is benefic and one of them is malefic; or if both of them are benefic, Shakat Yoga may not be formed in such horoscope.
Taking an example, suppose exalted Jupiter is placed in the ninth house of a horoscope in Cancer and Moon is placed in the second house in Sagittarius. Scorpio rises in the ascendant and Jupiter as well as Moon is benefic in the horoscope. Hence Shakat Yoga may not be formed in this case. On the contrary; such benefic placements may bless the native with good results related to finances, family, father, children, spiritual growth, profession, wealth and many other things.
Taking another example, suppose Jupiter is placed in the third house of a horoscope in Libra and Moon is placed in the eighth house in Pisces. Leo rises in the ascendant. Moon is duly malefic in the horoscope. Jupiter is partly benefic and partly malefic for horoscopes with Leo ascendant. Hence Shakat Yoga may be formed in this case and it may trouble the native with problems related to health, wealth, profession and a number of other problems. The concept of a planet being partly benefic and partly malefic has been explained in the book ‘Pitra Dosh – Ancestors are Calling (Revised Edition)’.
Once the formation of Shakat Yoga is confirmed in a horoscope, the next factor to check is its strength. The strength of this yoga is calculated through the placements of Jupiter and Moon in various signs, nakshatras and navamshas; as well as through the influences of other benefic and malefic planets on them. The overall theme of horoscope and running times (Mahadashas) also affect the strength of this Yoga.
Taking an example, suppose Jupiter is placed in the fifth house of a horoscope in Sagittarius, in Cancer navamsha of Moola nakshatra and exalted Moon is placed in the tenth house in Taurus, in Cancer navamsha of Rohini nakshatra. Both Jupiter and Moon are strong in their respective signs as well as in navamshas. Hence strong Shakat Yoga may be formed.
Looking at the running times; when Mahadashas (planetary periods) of benefic planets are in effect; malefic effects of Shakat Yoga may reduce. When Mahadashas of malefic planets other than Jupiter and Moon are in effect; malefic effects of this yoga may increase. When Mahadashas of Jupiter and Moon are in effect; the native may witness maximum damage due to Shakat Yoga.