If Mercury is in the 12th house without affliction, the person will be thrifty and able to hold on to his wealth. He will not meet with a great many expenses, and he will spend on good causes and charities, or for religious purposes. He will enjoy agood deal of sexual pleasure and sleep on fine beds. The significations of Mercury are harmed, and therefore the person may be troubled in thought or mind. He may have problems in educational matters or interruptions in his learning. The person's confidence and his nervous system may also come under attack. Ancient scriptures declare the person to be poor, cruel, and humiliated, but quite capable of keeping his word.

UCHCHA and SWAKSHETRA (exalted and own house). If Mercury is in Virgo or Gemini in the 12th house, the person is very fortunate in retaining his wealth and avoiding expenses and debts. He will not be bothered by thieves and robbers. He will be spiritual and meet with success if he takes to the path of enlightenment. He will also sleep on fine beds and enjoy a great deal of sexual pleasure in his life. He will have good hearing and vision. He will be successful in any remote foreign countries he may visit.

NEECHA (fallen). If Mercury is in Pisces in the 12th house, the person will not be able to hold on to his wealth. He will always face large debts and expenses. He will sleep in dilapidated beds and may reside in a low level after death. He will not receive much sexual pleasure. The person is troubled by thieves or secret enemies. There is no success in remote-far-off lands. The significations of Mercury are devastated by this placement. Therefore the person may lack confidence and mental stability and be highly nervous. Educational and intellectual pursuits are spoiled.

Source: «Ancient Hindu Astrology for the Modern Western Astrologer» by James Braha