Kena Upanishad 3.3-2

3.3-2

te tadajānanto devaḥ sāntarbhayāstadvijijñāsavaḥ agnim agragāminaṃ jātavedasaṃ sarvajñakalpam abruvan uktavantaḥ| he jātavedaḥ etad asmadgocarasthaṃ yakṣaṃ vijānīhi viśeṣato budhyasva tvaṃ nastejasvī kimetadyakṣamiti ||

Te, they—those gods who failed to know It, and were desirous of knowing It, but had fear in their hearts; agnim, to Fire, (lit.) who goes ahead (of all); and who is jātavedā, almost omniscient;footnote{Agni precedes all other deities (agre gacchati) in receiving oblations at sacrifices; and Jātavedā is one who knows (veda) all that is created (Jāta).} abruvan, said: O Jātavedā, you being powerful among us vijānīhi, thoroughly find out about; etat, this Yakṣa that is in our view; kim etat yakṣam iti, as to what this Yakṣa (venerable Being) is.