Hinduism is called Sanathanam, in other words the origin of Hinduism cannot be traced out. It has been as if from the beginning of human development in our part of the world. Hence, it is not easy to define what Hinduism is. Neither therefore is it possible to say who started it and who propogated it.
Left to surmise, I would say Hinduism is the life of the people of India extending from the Himalayas to Kanyakumari from time immemorial. When we say "life of the people", it is meant to identify the common traits in the people - like their food, habits, occupation, language, beliefs, customs, culture, etc. The life of the people with its untraceable origin growing, developing and extending to the present times, in short, can be called Hinduism.
Hinduism, in the strict sense, cannot be described as a religion. In fact, it is much more complex. It is the sum and substance of the life, history and growth of the people (who originally occupied the Indus Valley) from time immemorial upto the present. Therefore, Hinduism is called Sanathanam.
Hinduism (unlike other religions which are based on a specific book or set of books) evolved throughout the centuries with different schools of thoughts coming up with refreshing ideas, continually evolved through highly qualitative debates. Hinduism was not founded by any one person, nor was it revealed to any single person (or prophet). It was a continuous thought process of a country, whose inhabitants indulged in the healthy habit of finding out the meaning of life (or what could have been the motivating force in the very creation of world, life, etc.). It was more like a history of the Indian race with its social customs, having established certain code of ethics upon its citizens, started upon the quest to realize truth.
Unlike Christianity or Islam (which are of recent origin), the beginning of Hinduism cannot be traced. It is believed that Hinduism is related to the Vedas which are the original writings of ancient Indian people. These Vedas were produced long ago by the Aryans, who were originally inhabiting the "Saptha Sindhu" region in the beginning and later on migrated and occupied the whole of Indo-Gangetic plains. Gradually and subsequently, they spread throughout the northern part of the sub-continent (north of the Vindhyas). From then on, it was just a matter of time before their influence was carried over to the southern part of India.
The authorities for the Hindu way of life and the beliefs and attitudes, are the four Vedas, the one hundred and eight Upanishads, the Brahmasutras. The epics Mahabharata (with Bhagavath Geetha in it), the Bhagavatha and the Ramayana, the eighteen epics and the Sastras. Though there are inconsistencies and contradictions at various points in these works, Hinduism which is all pervasive, has become limitless and cannot be defined with limitations.
The Bhagavath Geetha which is inscribed in the great Epic, Mahabharata, deals with all the beliefs existing in the country till the date of the Geetha, and indicates the aspects of unity in these diverse beliefs and also indicates what is to be preferred. Hence, Bhagavath Geetha is the literature of the essence and truth of all beliefs with a guideline for discrimination and discretion.
The following narrates the above point fully: "Sarvasastramayi Geetha" (Geetha is the substance of all systematised knowledge given in the Sastras); "Ekam Sastram Devakiputra Geetham" (Of all the Sastras, the Geetha given by Lord Krishna (son of Devaki) is paramount and is most precise and discretionary. Kulasekara Azhwar (in his Mukundha Mala) says "Sakalamupanishadvakya Sampujya Manthram" the Bhagavath Geetha is adored by all the Upanishads. It is the essence of all Upanishads.
And what does the Geetha say? The Geetha says that God is indescribable. Divinity, which is another word for God, is beyond expression and beyond comprehension. As the divine force is all pervading (as it is the universal soul energy), its power and influence and its purpose and its work cannot be comprehended. There is no question of anybody seeing this divine omnipresent energy when it is even impossible for comprehension. But, if this were to be so, then what was the idea of pursuit of God or who can visualise God? The Geetha, however, addresses this issue also clearly - the path of bhakti yoga or total surrender to the Universal life energy - the Supreme.
In a constant quest to understand the above aspect, there developed two distinct schools of thoughts - one is Visishtadvaita and the other is Advaitha. These two philosophies are not completely apart and opposite. Both of them visualise the supreme or the supreme soul alike, but with a difference. While Advaitha gives an urge to man to search incessantly his identification with God, the Visishtadvaitha philosophy enables a person to achieve the same through the path of devotion (love and sympathy), to be mentally emotional, to be in a bliss of happiness and to be satisfied. When the former is agonising in its search for God (with frequent and sometimes with total disappointments), the latter never fails you. It affords you joy and satisfaction at every stage proportionate to the degree of intensity of your devotion. It is a sure path for peace and happiness as well as for the realisation of the truth, the path of Devotion or Bhakthi Yoga.
The founder and propagator of the Visishtadvaitha philosophy, Sri Ramanuja, had explained the universal truth and out duty as:
"Understand scientifically the Thatvatraya (the three aspects of the universe), namely the CHITH (the animals and the vegetation, which are living and growing), the ACHITH (the inanimate and the physical part of the universe) and the Eswara (the omnipresent energy pervading both the CHITH and the ACHITH). The Eswara is Tribhuvana Sundara with the three supreme aspects of truth, beauty and goodness. He who believes that the Eswara energy is all pervading is named a Vaishnava - such a person is of equanimity and loves and serves all. Such a person surrenders to the universal life force and hence he is selfless; he will never commit a sin being selfless and remains in a state of bliss unattached to the social bonds which is called Moksha or release from bondage or salvation."
That is the truth relating to Hinduism, God and Devotion. Understand this truth; follow this truth in life. This is the "Geetha Saram" - that is the essence of Geetha.
I do not wish to engage in the relative merits of various religions of the world. It is true that all religions preach selflessness, love and total supplication to the God (Christianity says Jesus is the path to the Father in Heaven and surrender unto Him - Islam says only Allah is the god and Mohammed is the Prophet and surrender unto Allah is the salvation - Hinduism (or Bhagavath Geetha) says surrender or total devotion to Lord Krishna (or Lord Vishnu) is the only way out of this samsara sagara (the cycle of birth and death).
But where Hinduism differs from the other two is on one salient point - Christianity or Islam does not say why a person is born in a particular way (that is rich, noble, a leader, devout, etc., as compared to a poor, murderer or a thief, etc.). Here, Hinduism offers a possible explanation - Karma. According to this Karmic theory, every soul has to undergo all the pleasures and sorrows alike till there is nothing more to experience before it can embark on its quest for the ultimate truth. But how does one know at what stage he is in. And that is why, the Geetha says, "Do your duty and leave the results to Me" and also further extolls "surrender and total devotion as the only way to salvation". Hence, by leading a contended life (that is in a semi-detached conditon - doing one's duty without caring for the results), loving and caring for others and also by constantly thinking and praying to Him, one can be on the right path. And the saints and spiritual teachers offer us the right direction and hence it is but necessary that one must approach a spiritual teacher and take his advice further on this. And that is again, "Saranagathi" or surrender - first to the Acharya (or one's spiritual teacher) who will lead the person to the ultimate truth or God.
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