Muṇḍaka Upaniṣad · 3.2.15
तिर्यगूर्ध्वमधःशयी रश्मिष्टस्पष्टान्व्योम । स एव धीरो विषदी वै प्राणान् संयम्य प्राणैर्जुहोत्याꣳशुमे
tiryag ūrdhvam adhaḥ śayī raśmiṣṭa-spaṣṭān vyoma | sa eva dhīro viṣadī vai prāṇān saṃyamya prāṇair juhoty aṃśum eva
Transversal, upward, downward, extended, with rays, in space, well-defined — that same serene one, free from sorrow, controlling the prāṇas, with the prāṇas offers as oblation to the Self that has rays.
Description of the omnipresent Self and the offering of prāṇa.
Tiryak ūrdhvam adhaḥ — transversal, upward, downward. In all spatial directions.
Śayī — extended, reclined. Present in all space.
Raśmiṣṭa-spaṣṭān — with rays, well-defined. Luminous, clearly established.
Vyoma — in space, in ether. Without support, omnipresent.
Dhīraḥ viṣadī — serene, free from sorrow. The result of realization.
Prāṇān saṃyamya — controlling the prāṇas. Prāṇāyāma as preparation.
Prāṇair juhoti — with the prāṇas offers. The interior sacrifice, the offering of vitality.
Aṃśum eva — to the Self that has rays. To the luminous Ātman.
The oblation is one’s own prāṇa, delivered in the fire of the Self.