Four Divisions of Men - Varnasrama Dharma / Caste System - Srila Prabhupada Bhagavad-gita 4.13

"According to the three modes of material nature and the work ascribed to them, the four divisions of human society were created by Me. And, although I am the creator of this system, you should know that I am yet the non-doer, being unchangeable."
His Divine Grace A.C. Bhaktivedanta Swami Prabhuapda gives class on the Bhagavad Gita verse Chapter 4 Text 14. Includes ecstatic kirtan lead by Visnujana Swami.