Lord Ganesha has been revered as one of the Shakti Devatha meaning, worshipping him would benefit the devotee in the same was as the worshiping Aadi Parashakti, Mahavishnu, Maharudra, Lalita.
Many stories in Purana attributes Lord Ganesha to intelligence and wisdom. Being married to Buddi and Siddhi, might also point at why the deity is the torchbearer for wisdom, mysticism, intelligence, power and Moksha.(salvation)
In another version of the Purana, they say that Wisdom and Intelligence are his consorts, eventually becoming his powers. Removing obstacles from to the process of knowledge gain, might also attribute to his Shakti of being the God of Knowledge pursuit.
Ganesha here represents the ego-bound Jiva. When the Lord comes, the Jiva, surrounded as it is with the murky cloud of ego, usually doesn’t recognize Him, and maybe even ends up arguing or fighting with Him! Therefore, it is the duty of the Lord, in the form of the Guru, to cut off the head of our ego! So powerful is this ego however, that at first the Guru’s instructions may not work, as Shiva’s armies failed to subdue Ganesha. It often requires a tougher approach, but, eventually the compassionate Guru, in His wisdom finds a way.
One of the seven chakras, Mooladhara, is supposed to have a treasure of knowledge from which the other chakras can be enlightened with the activation of Mooladhara, Kundalini.
Everything that’s depicted shouldn’t be taken at face value. Certain symbolism, and metaphors should be deciphered for the total understanding of what is, and why.
Ganesha is said to house both power of endowing wealth and knowledge. Siddhi is something that can be achieved through rituals pertaining to Atharvasheersha, and the instructions found in the Upanishad.
A story which explains the god’s association with intelligence and wisdom is his competition with Karthikeya to be the first to marry. They set up a challenge that whoever could first encircle the Earth would also find a bride first. Not wasting a second, Karthikeya swiftly mounted his blue peacock and immediately shot off around the world. Ganesha on the other hand, casually sauntered over to his parents’ house, embraced them and quoted the line from the sacred Vedas: “he who embraces his parents seven times (pradakshinas) gains the merit of encircling the world seven times”. Declared the winner, Ganesha promptly married not one but two daughters of Prajapati: Buddhi (Wisdom) and Siddhi (Success), with whom he had two sons: Kshema and Laabha.
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The principal scriptures dedicated to Ganesha are the Ganesha Purana, the Mudgala Purana, and the Ganapati Atharvashirsa. Brahma Purana andBrahmanda Purana are other two Puranic genre encyclopedic texts that deal with Ganesha.
Jai Ganesha.