One of the earliest Upanishads, the Chandogya Upanishad, is probably the first to boldly assert the brahmanatva ideal. Satyakama, the son of the maid servant Jabala, wanted to go to the great rishi Gautama for his education. Satyakama had never known a father. He asked his mother about it only to learn that even she did not know who his father was, as she had conceived him ‘while serving many people’. She suggested that as he was Satyakama and she Jabala, he could introduce himself as Satyakama Jabala. When Gautama asked Satyakama about his gotra, lineage, he told him what had transpired between him and his mother. Gautama said to Satyakama: ‘Son, no one other than a brahmana can speak the truth that you have spoken. Therefore, you are a brahmana, and I accept you.’ Here a brahmana is defined as one who is unflinching and uncompromising in his adherence to truth. Therefore, speaking the truth always — even amidst adversity — is the sign of a brahmana.
In the Brihadaranyaka Upanishad the great sage Yajnavalkya
declares King Janaka to be a brahmana,
for he is a knower of Brahman—the absolute undifferentiated cosmic Spirit, one
without a second, encompassing all existence: ‘That great, birthless Self is
undecaying, immortal, undying, and fearless; it is Brahman (infinite). Brahman
is indeed fearless. He who knows it as such certainly becomes the fearless
Brahman.’ Here elimination of the great fear of disease and death in the
presence of the knowledge of Brahman is considered the hallmark of brahmanahood.
In the same scripture Yajnavalkya provides the brilliant
woman sage Gargi with this unique philosophical-cum-mystical insight into the definition of a real brahmana:
‘One, O Gargi, who departs from this world without knowing this Imperishable (Reality), is
miserable, a kripana. But one, O Gargi, who departs from this world after knowing this Imperishable, is a
brahmana’ (Brihadaranyaka Upanishad 3.8.10).