Bhagavad Gita 4.25दैवमेवापरे यज्ञं योगिनः पर्युपासते।ब्रह्माग्नावपरे यज्ञं यज्ञेनैवोपजुह्वति ॥

Some Yogis who are devoted to Karma Yoga perform sacrificial rites to the shining ones or Devas (gods). The second Yajna is JnanaYajna or the wisdom sacrifice performed by those who are devoted to Jnana Yoga. The oblation in this sacrifice is the Self. Yajna here means the Self. The Upadhis or the limiting adjuncts such as the physical body, the mind, the intellect, etc., which are superimposed on Brahman through ignorance are sublated and the identity of the individual soul with the Supreme Soul or Brahman is realised. To sacrifice the self in Brahman is to know through direct cognition (Aparoksha Anubhuti) that the individual soul is identical with Brahman. This is the highest Yajna. Those who are established in Brahman, those who have realised their oneness with the Supreme Soul or Paramatma perform this kind of sacrifice. This is superior to all other sacrifices.