Rahu (North Node) and Ketu (South Node) are the soul purpose of life. Rahu is the future and Ketu is the past. Rahu shows what we want, it is obsession over those things where it sits in the birth chart. Ketu is our past mind conditioning, it shows where we already dealt with and we don’t want anymore. Rahu and Ketu axis shows that, in which area a person is immature and needs to be matured and in which area a person is matured. Where Rahu and Ketu axis fall in the birth chart it shows the most spiritual growth for the native in this life. Rahu and Ketu are the points where Sun (soul), Moon (mind), and earth (body) intersect in the sky. This point is very powerful and it forces us to think about who we are and what life is about. Rahu and Ketu are the forces which connect us with divine power.
Rahu (North Node) and Ketu (South Node) in astrology are the demons. In hindu mythology, the story of churning the ocean of milk is related to our subconscious mind. Rahu and Ketu are lunar Nodes which play a very important role in evolving the human consciousness. Rahu, and Ketu are the confusion, illusion, smoke and split thought of the mind. They always help to evolve consciously. They are always in the opposite axis therefore they are always 180 degrees apart. Although they are not a physical planet, they are the most influential forces in our life. Rahu/Ketu axis is the main force of karmic desire. Rahu is the head which always wants to eat and it is obsessed over those things where it is placed. It is our inner present desire for this life. Rahu is an obsession for those things where it is placed in the birth chart.
Ketu is the body without a head, it is our past life experience. There is detachment, disinterest for those things where Ketu placed in the birth chart.
So what happens when the Ketu/Rahu axis falls in the 6th and 12th house. Houses are the area of life. Rahu placement in the house shows the area of life in which we need to develop mentally and Ketu shows the area of life where we withdraw ourselves.
6th house: is the house of service, hard work, unpleasant things in life which we don’t like. It is the house of things in life which are most uncomfortable but have to deal with like enemy, disease, court, and litigation etc.
12th house: is the house of dreams, meditation, surrender, loss, isolation, prison, hospital, and spiritual practice etc.
This is actually good and constructive placement.
Rahu (North Node) in 6th house and Ketu (South Node) in 12th house axis fall in sixth house means the native is obsessed over hard work and withdrawn from surrender. In their childhood or in their past lives these people kept away from duties of daily life. Due to some reason like spiritual practice or any other reason which is written above. These people are obsessed over hard work and focused on life problems. Because 6th house is the house of hard work in life and there is conditioning around their mind that they may lose something if they don't work. Therefore they have fear and stress around that and they don’t want to make any mistake. These people are very practical in their approach in life. It is a placement of work and learning to improve through our own efforts. The 6th house rules obstacles and worries in life. Rahu in the 6th house gives strength to deal with. Here Rahu is teaching to confront situations and resolve problems. But due to stress and worry in life these people suffer might from health issues.
Ketu indicates that the 12th house is about letting go and surrender. The native feels emotionally difficult because of the painful experience of 12th house. They literally withdraw from the world. Ketu in 12th makes you easily connect with the higher metaphysical plane of life. These people are good at meditation and can look for higher knowledge of life (spiritualism).
Rahu (North Node) in Virgo and Ketu (South Node) in Pisces sign axis:
Rahu in Virgo sign: Rahu in Virgo people know how to discriminate, have practical sense, organized, and skillful. These people need to be careful not to be picky, critical, Judgmental, perfectionist and obsessive compulsive about things.
Ketu in Pisces sign: These people are dreamy, visionary, being Spiritual, they are committed to themselves, very intuitive and mystical. But they need to be careful not to be a drifter, unreal or Illusory or cloudy delusional kind of thinking.
Soul Purpose: These people needs to learn about devotion to service, discrimination, practicality, attention to detail, efficiency, organization, and analysis.
Other
Rahu (North Node) and Ketu (South Node) Articles
http://en.wikipedia.org/wiki/Rahu
http://en.wikipedia.org/wiki/Ketu_%28mythology%29
http://en.wikipedia.org/wiki/Lunar_node
http://en.wikipedia.org/wiki/House_%28astrology%29
http://en.wikipedia.org/wiki/Navagraha
http://en.mimi.hu/astrology/north_node.html