Incarnation of 6 Primary Gods

Murugan is incarnation of

1. Lord Brahma, 
2. Lord Vishnu, 
3. Lord Shiva, 
4. Lord Saraswathi, 
5. Lord Lakshmi and 
6. Lord Gowri 

http://freeglobaluniversity.blogspot.com/search/label/Three 

Subrahmanya represents the combination of six heads and twelve hands holds in his hands

1. Shakthi, 
2. Vajrayudha, 
3. trident , 
4. sword , 
5. protecting symbol, 
6. Shield, 
7. Bow, 
8. holy wheel , 
9. rope , 
10. cock , 
11. goad and 
12. symbol of boonteaches us that the ideal humanity is the perfect being who is not only a perfect yogi but also a great worker.

having the power of all the six Gods mentioned above and gives

1. Knowledge, 
2. Money, 
3. Potency, and 
4. the Power to succeed in any good endeavor.

Subrahmanya represents highest state to which a spiritual aspirant can evolve.
Etymologically Subrahmanya means ‗one who tends to spiritual growth of aspirants‘.

His six heads represent the five sense organs and the mind, which coordinates the
activities. When these are controlled, refined and sublimated man becomes a superman.

According to Yoga psychology, there are six centers of psychic energy.
1. They are Moolaadhaara(at the anus),
2. Svaadhishthaana (at the root of the sex organ),
3. Manipoora (at the navel),
4. Anaahata ( at the region of the heart),
5. Visuddha (at the throat),
6. Aajnaa (between the eye brows), Murugan Was Ray Born From Here of Shiva)
Perfect state of Consciousness Within Body
7. Sahasraara (at the top of the head) which is the destination for this energy.
(Shiva Shakti Stage) - Perfect state of Consciousness Without Body

When the yogi successfully raises his psychic energy to this top-most center he has a vision of Sivasakti.

The six heads indicate that he is the Source of
1. Six Vedanga and
2. six schools of philosophy.
3. Six rays or attributes - wisdom, dispassion, strength, Fame, wealth meaning wisdom and divine powers.
4 The war imagery and the six heads of Kartikeya indicates that if humans wish to lead themselves efficiently through the battle of life, they must always be alert lest they are shown the wrong path by crafty people with the six demonic vices: 

1. kaama (sex), 
2. krodha (anger), 
3. lobha (greed), 
4. moha (passion), 
5. mada (ego) and 
6. matsarya (jealousy).