Several pair of planets are considered as mutual enemies in Astrology. For example Sun and Saturn are considered as mutual enemies. Mars and Mercury are enemies. Mars and Saturn are enemies. Jupiter and Venus are enemies. But all these are not true, because having opposite qualities cannot be considered as enemity.

In general, A Man is having his own characteristics and qualities and a Woman is having her own characteristics and qualities. Even though most of their characteristics and qualities are naturally opposite to each other, we cannot consider them as mutual enemies.

Likewise, even though two planets are having exactly opposite characteristics, we cannot consider them as mutual enemies.

Taking Mars and Mercury into our account, Mars is the planet for our Blood, Anger, Quarrels, Less Intelligence, Physical Strength, significator of Medicine, Engineering fields, and Police, Military jobs. Mars mainly works with physical strength so a Policeman and Armyman could be having strong Mars influence.

Mercury is the planet for high Intelligence and less Physical work. Literature, Computer, Astrology, Programming, Accounting, Mathematics, Public Relationship, Marketing, Ecommerce like fields are the areas of Mercury. Upon seeing it carefully, Mercury related fields are mind related work. One have to think, analyse and apply his knowledge in the job.

Mercury influence us to be calm, study, and analyse for clear understanding. Mars influence us to be fast, anger, act without thinking. Both of their interest are in different directions. Mars influenced people are strong by their body strength where as Mercury influenced people are strong by their brain.

Upon considering their corresponding Lagnas, Mars owns Aries and Scorpio where as Mercury owns Gemini and Virgo. For Aries ascendant, Mercury become 3rd and 6th lord, usually gives malefic results. For Scorpio ascendant, Mercury becomes 8th and 11th lord, usually gives malefic results. Even though Mercury goes to 11th house, the house of benefits and profits, he reduce his 8th house nature and gives only less benefits.

At the same time, for a Gemini Ascendant, Mars is 6th and 11th lord, usually gives malefic results. For a Virgo ascendant, Mars is 3rd and 8th lord, also giving malefic results. Naturally opposite planets, even by the lordships they become opposite.

After all, every human needs the qualities of both Mars and Mercury in life. So, Mars ascendant people with Mercury benefically placed and Mercury ascendant people with Mars benefically placed will be blessed with both planet qualities in a beneficial manner.

Finally, if we consider them as mutual enemies, all Aries and Scorpion ascendant people could be fool as Mercury is not blessing them and Gemini and Virgo ascendant people could be anemic as Mars is not blessing them.