Mercury has a unique quality in that it is always colored by the other planets with which it is associated. It is influenced by the other planets because it absorbs their energies. And Mercury is rarely alone, so you rarely see the pure Mercury operating in a chart.
When Mercury is not negatively influenced by other planets it is the planet of intellect, skill, mathematics, computer science, education and creative expression. And more, it is clever, sharp and quick-witted when strong. It represents the nervous system and its condition shows the strength or weakness of a person’s nervous system and physical constitution.
When Mercury is in its ideal setting it is brilliant. People with such a Mercury speak very well, expressing their ideas in a clear and dazzling manner. They hold these impressive communication skills and are therefore able to charm and captivate people with their words.
This well placed Mercury is also capable of very clear discrimination – having the ability to choose what is right and what is wrong for themselves, making clear and positive decisions in their lives. This discrimination differs from the discrimination of Jupiter in that it is coming from a more intellectual place, through the analytical, logical mind rather than through intuition or wisdom. Mercury’s discrimination is the comprehension of information and more oriented toward the needs of the self, as opposed to Jupiter’s discrimination which is of higher knowledge and seeks to be discriminative in a more universal, justice-oriented manner.
The definition of a good Mercury is one which is favorable for the particular rising sign, placed in a friendly house, in a good Nakshatra with an effective distance from the Sun and favorably aspected. It is imperative that the landscape surrounding the Mercury be very supportive because it is so easily influenced by its environment.
Mercury naturally travels close to the Sun. When the Sun and Mercury are together it is called Chathura yoga, it is a combination which bring cleverness, brilliance and communication skills. It also supports competence in the area of business, it brings a certain amount of pragmatism and practicality to the Mercury.
However, Mercury becomes combust the Sun when it is within 10 degrees of the Sun. This combustion makes the Mercury, nervous, anxious and restless – it makes the person jittery because the fieriness of the Sun is affecting the mind, Mercury cannot handle this much energy. But when the combustion is within 3 degrees, Mercury becomes brilliant – it borrows the brightness and shining of the Sun. When their distance is between 10 and 20 degrees the jitteriness subsides a bit. When the Mercury is beyond 20 degrees of the Sun, but still in the same house, then it is called Budha/Madhurya yoga. Mercury is far enough from the Sun to be able to flourish on its own while still getting some of the brightness of the Sun’s influence. Madhurya refers to honey - the person will have speech which possesses the smoothness, fluidity and compelling nature of honey. It is not just sweet speech, comforting to the ears but also a rich, delicious meal for the intellect.
When Mercury is well placed it brings good writing skills, scholarliness and journalistic abilities.
When Mercury is connected with Saturn it brings skills in the areas of computers for the sake of analysis and statistics. It brings to the intellect the ability to analyze, qualify and quantify. When the association is as a benefic it sharpens the intellect and is therefore good for going deep into research and invention.
When Mercury is connected with Jupiter it brings theological knowledge. The spiritual wisdom of Jupiter is able to be expressed in a very logical, cerebral manner. It brings the mind into the area of philosophy and spirituality. It explains and gives form to the spiritual activities.
When Mercury is connected with Mars it brings technical skill, engineering abilities, mechanical expertise. In addition it brings skill for debate and dispute and brings a certain type of cleverness.
When Mercury is connected with the Moon it brings the ability to be appreciated by others. People will feel that this person has vision and ideas, as well as a social capability. In the workplace, this person will be hired because of their communication/people skills. Mercury will express, make suggestions, share ideas and possibilities. It is also very creative.
When Mercury is connected with Venus it brings artistic and creative expression. It supports all areas of creative intellect.
When Mercury is connected with Ketu it brings instability of the mind – one day it can be fixed on one idea and the following day be questioning that same idea. The person may revisit thoughts and choices over and over, questioning and doubting themselves. When the Ketu is very strongly influencing the Mercury it can bring nervousness and anxiety. It can create certain complexes based in fear like phobias.
When Mercury is connected with Rahu it brings confusion to the mind. The person may have false imagination, fantasies, illusions. They cannot see things realistically or clearly.