Bhagavad Gita 4.13

चातुर्वर्ण्यं मया सृष्टं गुणकर्मविभागशः।
तस्य कर्तारमपि मां विद्ध्यकर्तारमव्ययम्।।4.13।।

Chaturvarnyam maya srishtam gunakarmavibhagashah
Tasya kartaramapi mam viddhyakartaramavyayam

Simple meaning, written by AII created the four social classes based on qualities and work; even though there is a doer, know that I am the eternal, unchanged doer.

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