Brihadaranyaka Upanishad 2.4.1-3
Now when Yagnavalkya was going to enter upon another state, he said: "Maitreyi, verily I am going away from this my house (into the forest). Forsooth, let me make a settlement between thee and that Katyayani (my other wife)." Maitreyi said: "My Lord, if this whole earth, full of wealth, belonged to me, tell me, should I be immortal by it?" "No," replied Yagnavalkya; "like the life of rich people will be thy life. But there is no hope of immortality by wealth." And Maitreyi said: "What should I do with that by which I do not become immortal? What my Lord knoweth (of immortality), tell that to me."