If Mercury is in the 6th house, the person will have strength to defeat his enemies and competitors. He may have a good knowledge of health matters. There will be obstacles in educational pursuits. However, the person is outwardly intelligent and well respected. He will be interested in expressing and proving his point of view, and, is very talented in debating issues. Because he is so concerned with being right, he may be known as a quarrelsome person. He will be quite proud and enjoy showing off or bragging about himself. There may be a speech problem in childhood which improves in time. The person obtains good jobs with fine pay. Daily work may involve any intellectual or communications activity. The person will write many letters, and if Mercury is well aspected, he will become an author. If Mercury is afflicted, there may be nervous disorders, speech defects, mental problems, and poor health. The person would be too easily excitable or rash under many circustances. There would also be difficulties in the sphere of job and subordinates, etc.

UCHCHA and SWAKSHETRA (exalted and own house). If Mercury is in Virgo or Gemini in the 6th house, the person will defeat his enemies and rise above his competitors. He will be vital and healthy. The person is calm and stable, and has a strong nervous system. He will excel in convincing others to accept his point of view. He may be a fine writer and may author several books. The person is capable of mastering minute detail work. He will gain from his uncle and cousins. He may also benefit from subordinates, co-workers, and tenants. He may be involved in the medical field.

NEECHA (fallen). If Mercury is in Pisces in the 6th house, the person will have health problems. He may have slight energy or a weak constitution. There may be nervous disorders or mental problems. There may also be lung or breathing problems. There may be many enemies throughout his life, and the person has no ability to defeat them. Nor does he rise above his competitors. Because Pisces rules the feet, there may diseases in this part of the body.

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