Third house is the house of courage. Mars is the epitome of courage and fearlessness. This is the natural house for Mars. Having said that vedic astrology is a classic case of paradox. The planets which are the significators of a house do maximum damage for matters of those house. This phenomenon is called Karaka Bhavo Nashya in vedic astrology. This sanskrit term implies the significators(karaka) of a horoscope house(bhava/bhavo) destroy(nashya/nashto) the fruits associated with those house. That does not necessarily mean native will never gain from placement of that particular planet but some or the other aspect of that house would be adversely affected. In this case Mars in third house would adversely affect either communication skills, relationship with siblings/neighbors, short/long travels, courage or other matters which are defined by third house.

     Mars in third house would give reckless nature. It also makes native an aggressive communicator and one who is not afraid to speak his mind. Someone who loves calling things as they are. While they don't make many friends with such attitude it is necessary that such people exists in the society. Mars in third house makes a native critical and intolerant to the evils in the society. He/She would do best to highlight the evils in the society and try to change the behavior of the society. Naturally such people tend to have difference of opinion with friends, siblings, neighbors and society who do not like to be shown the mirror. This placement of Mars has been known to produce quite a few courageous writers and journos who fearlessly expose wrong doers. This gives them quite a few enemies. They also need to travel a lot and most of the time those travels incur loss to them. The aspect on sixth house gives a lot of enemies and aspect on ninth house gives frequent travels and monetary loss due to them. The aspect on tenth house maybe good provided horoscope sign is supportive. General prediction is aspect on tenth house gives boost to career but produces quite a few enemies at workplace due to the competitive nature of the person.

     Mars in third house gives courage and fearlessness. It also gives the much needed critical thinking as third house also rules over analytical skills. Those with Mars in third house can be successful in journalism, media and press jobs. They can be wonderful writers as well who write painful truths and show mirror to the society. Natives are advised to avoid picking fights with influential people. Also they should never take their enemies lightly.