The following essay has been translated from Bengali and is reproduced from Swami Vivekananda’s Complete Works, 6: 181-86.
For the Hindus, by the word “Shastras” is meant the Vedas which are without beginning or end. In matters of religious duty the Vedas are for them the only capable authority.
The Puranas and other religious scriptures are all denoted by the word "Smriti". And their authority goes so far as they follow the Vedas and do not contradict them.
Truth is of two kinds:
(1) that which is known through the five ordinary senses we humans have, and by reasoning based thereon;
(2) that which is known through the subtle, supersensuous power of Yoga.
Knowledge acquired by the first means is called science; and knowledge acquired by the second is called the Vedas.
The whole body of supersensuous truths, having no beginning or end, and called by the name of the Vedas, is ever-existent. The Creator Himself is creating, preserving, and destroying the universe with the help of these truths.
The person in whom this supersensuous power is manifested is called a Rishi, and the supersensuous truths that he or she realizes by this power are called the Vedas.
This Rishihood, this power of supersensuous perception of the Vedas, is real religion. And as long as this does not develop in our lives, so long is religion a mere empty word to us, and it is to be understood that we have not taken yet the first step in religion.
The authority of the Vedas extends to all ages, climes and persons; that is to say, their application is not confined to any particular place, time, and persons.
The Vedas are the only exponent of the universal religion.
Although the supersensuous vision of truths is to be met with in some measure in our Puranas and Itihasas and in the religious scriptures of other races, still the fourfold scripture known among the Aryan race as the Vedas being the first, the most complete, and the most undistorted collection of spiritual truths, deserve to occupy the highest place among all scriptures, command the respect of all nations of the earth, and furnish the rationale of all their respective scriptures.
With regard to the whole Vedic collection of truths discovered by the Aryan race, this also has to be understood that those portions alone which do not refer to purely secular matters and which do not merely record tradition or history, or merely provide incentives to duty, form the Vedas in the real sense.
The Vedas are divided into two portions, the Jnana-kanda (knowledge-portion) and the Karma-kanda (ritual-portion). The ceremonies and the fruits of the Karma-kanda are confined within the limits of the world of Maya, and therefore they have been undergoing and will undergo transformation according to the law of change which operates through time, space, and personality.
Social laws and customs likewise, being based on this Karma-kanda, have been changing and will continue to change hereafter. Minor social usages also will be recognized and accepted when they are compatible with the spirit of the true scriptures and the conduct and example of holy sages. But blind allegiance only to usages such as are repugnant to the spirit of the Shastras and the conduct of holy sages has been one of the main causes of the downfall of the Aryan race.
It is only the Jnana-kanda, or Vedanta, that has for all time commanded recognition for leading people across Maya and bestowing salvation on them through the practice of Yoga, Bhakti, Jnana, or selfless work; and as its validity and authority remain unaffected by any limitations of time, place or persons, it is the only exponent of the universal and eternal religion for all humanity.
The Samhitas of Manu and other sages, following the lines laid down in the Karma-kanda, have mainly ordained rules of conduct conducive to social welfare, according to the exigencies of time, place, and persons. The Puranas etc. have taken up the truths imbedded in the Vedanta and have explained them in detail in the course of describing the exalted life and deeds of Avataras and others. Moreover, in order to teach us, they have each emphasized some out of the infinite aspects of the Divine.
But when by the process of time, fallen from the true ideals and rules of conduct and devoid of the spirit of renunciation, addicted only to blind usages, and degraded in intellect, the descendants of the Aryans failed to appreciate even the spirit of these Puranas etc. which taught people of ordinary intelligence the abstruse truths of Vedanta in concrete form and diffuse language and appeared antagonistic to one another on the surface, because of each inculcating with special emphasis only particular aspects of the spiritual ideal—
And when, as a consequence, they reduced India, the fair land of religion, to a scene of almost infernal confusion by breaking up piecemeal the one Eternal Religion of the Vedas (Sanatana Dharma), the grand synthesis of all the aspects of the spiritual ideal, into conflicting sects and by seeking to sacrifice one another in the flames of sectarian hatred and intolerance—