Vajrasuci Upanishad is about removal of ignorance for the realization of the truth. This minor Upanishad from Samaveda takes the smiley of cast system for identifying the quality of a real sadaka. This Upanishad is known to academic circles but not popular among masses. This can be the reason that it was not found quoted by scholars to put up a case against cast prejudice that plague Hindu society.

Vajrasuci Upanishad starts with the common misconceptions as to who is a Brahmana, the privileged ones, who alone is entitled to have the highest knowledge of Brahman.

Since jiva as subtle body pass through many birth; jiva cannot be the Brahmana. Then, is it the body Brahmana? The body is made up of five elements which is same for chandala, kshatriya and all other cast; so the body cannot be the Brahmana.

Then, is it a class or cast. It cannot be. Since many Rishis, the gem of mankind were born to lower cast and even to animals and inanimate objects; so, cast and class cannot be criteria for Brahmana. Rishya Sringa was born to a deer, Kausika to Kusa grass; Jambuka of Jackal, Valmiki of Valmika; the great Vyasa of a fishermans daughter, Vasista of a celestial nymph, Agastya of a water pot. Since many from lower class of society can be greatest spiritual luminaries of all times, cast and class cannot be criteria for Brahmana.

Is it the Knowledge that makes one Brahmana? Since many in Kshatriya and other cast have the wealth of knowledge and that did not lead them to highest truth; Knowledge cannot be criteria for Brahmana. Then is it, Karma that make one Brahmana? Since Karma binds all being, it cannot be. Then is it doing dharma (virtuous action) ? Since, people from all cast and class do virtuous act; the virtuous act cannot be criteria for Brahmana.

Then who actually is it a Brahmana? One who know Atma, which is without a second, that is devoid of class, action, that is free from fault of six strains (hunger, thirst, grief, confusion, old age, death) and six changes ( birth, existence etc ); That, he is of the nature of truth, knowledge, bliss, eternity. Who is free from worldly objects, passion, pride, etc. He, who have all these qualities, irrespective of which cast and class he belongs, alone is a Brahmana.