Rāhu & Ketu in the Houses
Since they are always a pole/axis 180º apart from one another, their presence in a house gives prominent to the theme of that house’s axis. The way that they activate the axis is this: Ketu pulls from the house in which it sits, and gives what it pulls to Rāhu, who pushes it out into the house in which it sits. It is like Ketu dropping an anchor and drilling into the house it occupies, then supplying the oil and ore mined from it to fuel Rahu’s expansion within its house.
If the house Ketu sits in has a lot of affinity with Ketu, that “dropping of anchor and drilling” will produce a very good effect, granting a lot of depth and penetration into the subjects of that house. Otherwise, Ketu has a draining affect on its house.
If the house in which Rāhu sits can do well with the output of volume and power Rāhu brings, it creates a very good effect, granting a great deal of strength and power in that house. Otherwise, Rāhu has a very excessive affect on its house.
Rāhu Ketu reveal the life-lesson, the major lesson one must learn in this lifetime. The lesson is to harmonize and synthesize the polarities on the axis Rāhu and Ketu occupy. In relation to that axis, Rāhu will show where one needs to be more conservative and strict, Ketu shows where one needs to be more liberal and forgiving.
One thing to be noted is that if Rāhu or Ketu is in rāja-yoga or conjoined with a planet with a significantly positive yoga the standard interpretation has to be altered, for in rāja-yoga Rāhu and Ketu do not symbolize bad effects.