Verse
शुक्लकृष्णे गती ह्येते जगतः शाश्वते मते ।एकया यात्यनावृत्तिम् अन्ययावर्तते पुनः ॥
These are the bright and the dark paths (called the path of the gods and the path of the fathers in the Upanishads); by the one he departs who does not return, by the other he who returns again.
Gītā 8·26