"ओँ तत्सत्" मन्त्र माहात्म्यम्The greatness of the mantra oṁ tat sat
Verse 159
निगमागमतन्त्राणां सारात्सारतरो मनुः । ओं तत्सदिति देवेशि तवाग्रे सत्यमीरितम् ॥ १५९ ॥
nigamāgamatantrāṇāṁ sārātsāratarō manuḥ | ōṁ tatsaditi dēvēśi tavāgrē satyamīritam || 159 ||
Translation
Of the Nigamas, Āgamas and Tantras this mantra is the essence of the essence: oṁ tat sat, O Queen of the gods. I have told you the truth to your face.
Word by word
- nigama
- of the Nigamas
- āgama
- (āgama) Āgamas
- tantrāṇāṁ
- and Tantras
- sārāt
- than the essence
- sāra
- the essence
- tarō
- (taraḥ) more
- manuḥ
- the mantra
- ōṁ
- oṁ
- tat
- tat
- sad
- (sat) sat
- iti
- thus
- dēvēśi
- O Queen of the gods
- tava
- of you
- agrē
- (agre) before
- satyam
- the truth
- īritam
- is told
Meaning
The Nigama and Āgama are the two classes of revealed teaching, and the Tantra is the third term here. All of them are said to have this at their core.

Commentary
Hariharānanda Bhāratī’s Sanskrit commentary, translated
See the commentary on verse 158.