Chapter 4 · Knowledge and Renunciation of Action · Krishna said
Bhagavad Gita 4.13 — Four orders by quality and work
चातुर्वर्ण्यं मया सृष्टं गुणकर्मविभागशः। तस्य कर्तारमपि मां विद्ध्यकर्तारमव्ययम् ॥
cāturvarṇyaṃ mayā sṛṣṭaṃ guṇakarmavibhāgaśaḥ | tasya kartāramapi māṃ viddhyakartāramavyayam ||
Meaning
I created the four orders of society according to people's qualities and work. Though I am their creator, know Me to be the non-doer and unchanging.