KENA UPANISHAD · 3/2

तद्धैषां विजज्ञौ तेभ्यो ह प्रादुर्बभूव तन्न व्यजानत किमिदं यक्षमिति ॥

taddhaiṣāṃ vijajñau tebhyo ha prādurbabhūva tanna vyajānata kimidaṃ yakṣamiti ॥

The Eternal knew their thought and appeared before them; and they knew not what was this mighty Daemon.