Chapter 5, Verse 19
Part of 5: Karm Sanyās Yog — कर्मसंन्यासयोगइहैव तैर्जितः सर्गो येषां साम्ये स्थितं मनः। निर्दोषं हि समं ब्रह्म तस्माद्ब्रह्मणि ते स्थिताः॥
ihaiva tair jitaḥ sargo yeṣhāṁ sāmye sthitaṁ manaḥ nirdoṣhaṁ hi samaṁ brahma tasmād brahmaṇi te sthitāḥ
Even here in this world, those whose minds rest in reality overcome birth; Brahman is indeed spotless and real; therefore they are established in Brahman.
When the mind gets rooted in eanimity or evenness or eality, when it is always in a balanced state, one coners birth and death. Bondage is annihilated and freedom is attained by him. When the mind is in a perfectly balanced state he overcomes Brahman Himself, i.e., realises Brahman. Brahman is ever pure and attributeless and so He is not affected even though He dwells in an outcaste, dog, etc. So He is spotless. He is homogeneous and one, as He dwells eally in all beings.