What does it mean to have 7th lord in 6th house?

Please Note: This is general prediction and results may vary based on aspects | conjunction | strength of planet, rashi placed etc.

As we know Sixth house is First of Dusthasthana Houses (houses ==> 6, 8 and 12) and Second of Upachaya Houses (houses ==> 3, 6, 10 and 11). It represents things like diseases, debts, obstacles, enemies, disputes, daily routine life, colleagues at workplace etc. One thing to remember here is that it is one of Upachaya Houses which improve with time. It means any planet in these houses improves in results with age and real good result is seen from a person’s 30s or 36s. Also, all the malefic planets provide very good results in Upachaya Houses but results may be seen in 30s or 36s.

Also, as we know about Seventh house, it is house of marriage, spouse, marital happiness, market place, other people (masses), business partnerships, agreements, etc.

दारेशे रिपुभावस्थे भार्या तस्य रूजान्विता।

स्त्रिया सहाअ्थ वा वैरं स्वयं क्रोधी सुखोज्जितः।।

When 7th lord comes in 6th house it means it is 12 from its house [bhavat bhavam]. This is considered the most difficult position for the 7th lord to be in. This combination also produces a very greedy, cunning, and selfish character.