Lord Siva is not only an aspect of the Triune Godhead the destruction- regeneration aspect-he is the highest Cosmic logos. The Siva LINGAM is a 'natural' Hindu symbol, which is the mathematical form of an ellipsoid. It is natural because it not only represents a reality but is the actual vehicle of Power within that reality. It symbolizes SivaSakti, that is, the primary polarity principle of positive and negative forces. On this principle of opposites the whole universe is founded.
Naagendrahaaraaya trilochanaaya, Bhasmaangaraagaaya mahesvaraaaya Nityaaya sudhaaya digambaraaya, Tasmai 'na' kaaraaya namah Shivaaya.
Salutations to Lord Siva who exists in the sound 'Na'. He wears snakes as garland, is three-eyed, his body is smeared with ash, he is pure, wears the sky as his attire'
The ultimate reality, the Absolute, or Brahman, or God has no polarity, no pairs of opposites : all principles are balanced and harrt'onittd within it. Therefore the ultimate reality is represented by the most perfect mathematical figure, the sphere. If the center or focal point of the sphere divides itself into two, we get the ellipsoid. So this form gives a symbolic representation of the primary pair of opposites out of the original harmonious one. And from this duality comes all manifestation, all creation, all the multiplicity of things in the universe. The LINGAM is therefore the basic form lying at the root of all creation, as 'OM' is the basic sound.
From one Brahman emerges SIVA-SAKTI, the father and mother of all that is. The male or positive aspect represents Consciousness, the female or negative aspect symbolizes power. Both are necessary for creation or manifestation in the planes of matter.