Shvetashvatara Upanishad Verse 1.14
Sanskrit
स्वदेहमरणिं कृत्वा प्रणवं चोत्तरारणिम् ।
ध्याननिर्मथनाभ्यासाद् देवं पश्येन्निगूढवत् ॥ १४॥
Transliteration
svadeham araṇiṃ kṛtvā praṇavaṃ cottarāraṇim |
dhyānanirmathanābhyāsād devaṃ paśyen nigūḍhavat || 14 ||
Translation
By making one’s own body the lower friction-stick and the Pranava (Om) the upper friction-stick, and by practicing the friction of meditation, one should see the hidden God, as it were.

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