Reason why Goddess Lakshmi and Lord Ganesha are worshipped together in Hinduism, is a million dollar question and there are some reasons behind this.
Firstly, Goddess Lakshmi is regarded as the deity of wealth, prosperity, and abundance, and Lord Ganesha is considered to be the remover of every obstacle and the Lord of new initiations. Worshipping them together is believed to beckon success, total prosperity, and good fortune while removing all types of obstacles that may block any progress.
Secondly, Lord Ganesha is taken to be the son of Goddess Parvati, who is an incarnation of Goddess Shakti too. Goddess Lakshmi is also regarded to be a manifestation of Goddess Shakti. Thus, worshipping these two manifestations of Shakti is believed to bring blessings from the feminine divine energy. And it is embodied by both the deities.
Thirdly, it is taken for granted that Lord Ganesha is pleased with the worshipping of Goddess Lakshmi, and Goddess Lakshmi also shows her pleasure by the worship of Lord Ganesha. Thus, worshipping them together is believed to find a powerful way to win the blessings and grace of both the powerful deities.
Reason why Goddess Lakshmi and Lord Ganesha are worshipped together is a way of seeking their blessings by all means and having their guidance in both material and spiritual aspects of life. At the same time it is also honoring the divine feminine energy that they both embody so to say.
Is there any Special Reason?
Yes, there are some special reasons why Goddess Lakshmi and Lord Ganesha are worshipped together all the way.
One reason may be this that it is Lord Ganesha who is believed to be the remover of obstacles and the lord of new beginnings too. In Hinduism, it is believed that before initiating any new endeavor or any kind of undertaking, one should seek the blessings of Lord Ganesha to ensure that the journey is sure to be smooth and free from all obstacles. Worshipping Lord Ganesha along with Goddess Lakshmi, who is known in Hinduism as the deity of wealth and prosperity, it is believed that one can overcome any kind of challenges that may arise while seeking mundane wealth and overall success.
Another reason is that Goddess Lakshmi is the consort of Lord Vishnu. He is one of the three main deities in Hinduism. The other ones are Lord Brahma and Lord Shiva. Lord Ganesha is the son of Lord Shiva and Ma Parvati, and is also worshipped as a deity in his own right. By worshipping both Goddess Lakshmi and Lord Ganesha together, devotees go for the blessings of both the feminine and masculine energies, and honor the unity and amalgamation of all aspects of the very divine.
In addition, it is believed that if Goddess Lakshmi and Lord Ganesha are worshipped together, they can help to balance both the material and spiritual wealth. Again Goddess Lakshmi is associated with material prosperity; Lord Ganesha is linked with wisdom, knowledge, and spiritual development. Going for the blessings of both the deities together, devotees can opt for both material success and spiritual growth and fulfillment to the fullest.
Finally it can be said that worshipping Goddess Lakshmi and Lord Ganesha together is a way of winning their blessings and guidance in all aspects of life, this is the reason why Goddess Lakshmi and Lord Ganesha are worshipped together.
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Well there could be so many tales and reasons behind lord Ganesha and goddess Laxmi being worshipped together out of 36 crore gods and goddess in Hinduism, but this one sounds the most rational to me. Hinduism believes that each god and goddess have different importance and worshiped for a different reason so let me first talk about their individual importance in Hinduism. As wealth is the crucial element of any civilization, we have a supreme deity to be worshipped and bestow the wealth and prosperity upon the devotees, goddess Laxmi is the supreme being worshipped for affluence and riches.
The son of almighty Shiva, who drank the venom created from the churning of the ocean to save world from effects of venom and which made his throat turn blue, is one of the most worshipped god in hindu dharma. Ganesha is widely revered as the remover of obstacles, the patron of arts and sciences and the deva of intellect and wisdom. As the god of beginnings, he is honoured at the start of rituals and ceremonies. Ganesha is most commonly revered as the god of intellect.
Wealth without intellect will only result in misusing of wealth, one must first acquire the intelligence to spend the wealth in the right manner and then only one can multiply that wealth and prosper. So worshipping the patron of wealth with patron of intellect could be the best possible way of acquiring two indispensable things in life and that could be the evident reason of worshipping lord Ganesha and goddess Laxmi together.