Mahabharata 5.43.26

5.43.26

dānamadhyayanaṃ yajño lobhādetatpravartate |
satyātpracyavamānānāṃ saṃkalpo vitatho bhavet || 26 ||

"Sanat-sujata, 'There is but one Brahman which is Truth's self. It is from ignorance of that One, that god-heads have been conceived to be diverse. But who is there, O king, that hath attained to Truth's self or Brahman? Man regardeth himself wise without knowing that One Object of knowledge, and from desire of happiness is engaged in study and the practices of charity and sacrifices. They have deviated from Truth (Brahman) and entertain purposes corresponding (with their state) and hence relying on the truth of Vedic texts thereof perform sacrifices. Some perform (or attain the object of) sacrifices by the mind (meditation), some by words (recitation of particular prayers, or Yapa); and some by acts (actual consummation of the Yatishtoma and other costly rites). The person, however, who seeketh Brahman through Truth, obtaineth his desired objects at home. When however, one's purposes become abortive (through absence of knowledge of Self), one should adopt vows of silence and such like, called Dikshavrata. Indeed, Diksha cometh from the root Diksha, meaning the observance of vows. As regards those that have knowledge of Self, with them Truth is the highest object of pursuit.'