Swami Sivananda is chanting the shanti mantra and talks about the Isha Upanishad.
The Isha Upanishad (Devanagari: ईशोपनिषद् IAST īśopaniṣad) is one of the shortest Upanishads, embedded as the final chapter (adhyāya) of the Shukla Yajurveda. It is a Mukhya (primary, principal) Upanishad, and is known in two recensions, called Kanva (VSK) and Madhyandina (VSM). The Upanishad is a brief poem, consisting of 17 or 18 verses, depending on the recension.
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