In Vedic astrology you can not assign fixed results to any planet occupying any Bhava / house and it entirely depends on the complete judgement of horoscope.
In Vedic astrology every planet is supposed to give results on three prospects:
(1) Physical Prospects: If you find Jupiter ill disposed in Ekadashansh Chart (D11), Shodashansh Chart (D16) and Trishmansh Chart(D30) only then being in 12th Bhava / house it will prove inauspicious regarding, financial attainments, acquisition of valuable assets and vehicles and sound health but from this position it will aspect 4th, 6th & 8th houses so it gives protection & narrow escapes from major accidents.
(2) Mental Prospects: If in any horoscope it is found that Jupiter occupying 12th house is well disposed in the Kendras of Saptvinshansh Chart (D27) in its own or exaltation sign then under this position Jupiter aspects 4th, 6th & 8th Bhavas / house in main chart the it gives one satisfaction, power to grapple with his inner foes such as Kaama (desires leading to destruction), Krodha (anger), Lobha (greediness), Moha (excess of affection leading to the loss of sense of judgement), Mada (increased ego leading to madness) & Maya (Illusion) and here it gives instinct to practice occult as it also aspects 8th Bhava / house in one’smain chart.
(3) Spiritual Prospects: If in any horoscope it is found that Jupiter occupying 12th house is well disposed in Vinshansh (D20) & Panchmansh (D5) charts in its own or exaltation sign in kendra / trikona and in main chart it occupies 12th house (Moksh Sthana / the house of liberty) and from here it aspect 4th house, 6th house & 8th house then it gives (1) Eternal joy or Aatmik Sukh i.e. Sat, Chit & Ananda or one here it leads one towards Sacchidanad Parmatma as it aspects 4th house, 6th house also stands for debts and in terms of spirituality it clears all the three major debts debts such as Matri rina, Pitra rina & Achary rina and this position makes one free from cycle of births on earth, in this case Jupiter also aspects 8th house then under such condition it brings one from occult (8th) house i.e. Maya (darkness of illusions) to eternal light as Jupiter is Guru and it removes every kind of darkness and brings one from Tamsik darkness to satvik light.
(4) If in any horoscope Jupiter in 12th house is strong as described under (2) & (3) one becomes Guru and enlightens others also.
(5) Jupiter in 1st, 2nd, 8th, 10th or 12th Bhava / House in any horoscope makes on Guru.
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