MUṆḌAKA UPANISHAD · 1.1.4

तस्मै स होवाच ।
द्वे विद्ये वेदितव्ये इति ह स्म
यद्ब्रह्मविदो वदन्ति परा चैवापरा च ॥ ४॥

tasmai sa hovāca ।
dve vidye veditavye iti ha sma
yadbrahmavido vadanti parā caivāparā ca ॥ 4॥

To him thus spoke Angiras: Twofold is the knowledge that must be known of which the knowers of the Brahman tell, the higher and the lower knowledge.