Mercury (Budh) is the planet of communication, writing, and intellect. The 2nd house rules speech. The 7th house rules public dealings.
When Mercury sits in either of these houses, the person is blessed with a terrifying command over language. They are not just good writers or speakers; their words are explosive. When they write an article, give a speech, or argue a point, every single word acts like "barood" (gunpowder). They can destroy an opponent's argument or ignite a massive public movement with just a few sentences.
The VAYOM Warning: If you have this placement, your pen is a weapon. Use it to spread truth and knowledge. If you use your explosive words to spread lies or defame innocent people, the gunpowder will eventually blow up in your own face.