KAṬHA UPANISHAD · 1.1.13

स त्वमग्निँ स्वर्ग्यमध्येषि मृत्यो
प्रब्रूहि त्वँ श्रद्दधानाय मह्यम् ।
स्वर्गलोका अमृतत्वं भजन्त
एतद् द्वितीयेन वृणे वरेण ॥ १३॥

sa tvamagnim̐ svargyamadhyeṣi mṛtyo
prabrūhi tvam̐ śraddadhānāya mahyam ।
svargalokā amṛtatvaṃ bhajanta
etad dvitīyena vṛṇe vareṇa ॥ 13॥

“Therefore that heavenly Flame which thou, O Death, studiest, expound unto me, for I believe. They who win their world of heaven, have immortality for their portion. This for the second boon I have chosen.”