“Not by birth does one become an outcaste, not by birth does one become a brahman. By one's action one becomes an outcaste, by one's action one becomes a brahman.”
§ 136
Source: Pali Canon, Sutta Pitaka, Khuddaka Nikaya (Minor Collection), (Suttas falling down)
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Gautama Buddha 121
philosopher, reformer and the founder of Buddhism -563–-483 BCRelated quotes

“One does not become fully human painlessly.”
Foreword to Existential-Phenomenological Alternatives for Psychology (1978) by Ronald S. Valle and Mark King

“To gulp down anger is the most courageous act one can perform. One who does it becomes humble.”
5:1857.
Lord Meher (1986)

Women Saints of East and West
“Only by being a man or woman for others does one become fully human.”
'Men for Others' http://www.creighton.edu/CollaborativeMinistry/men-for-others.html, 1973, Valencia, Spain
“Vivekananda often asserted that only in becoming a ṛṣi does one understand the scripture properly.”
Source: The Nature and Authority of Scripture (1995), p. 23
Context: Vivekananda often asserted that only in becoming a ṛṣi does one understand the scripture properly. His argument appears to be that as products and records of direct perception, these texts were not written for the intellect, or for understanding through a process of rational inquiry and analysis. They become meaningful only when one has lifted oneself to the same heights of perception.