Bhagavad Gita Chapter 17 Verse 24 भगवद् गीता अध्याय 17 श्लोक 24 तस्मादोमित्युदाहृत्य यज्ञदानतपःक्रियाः। प्रवर्तन्ते विधानोक्ताः सततं ब्रह्मवादिनाम्।।17.24।। हिंदी अनुवाद - स्वामी रामसुख दास जी ( भगवद् गीता 17.24) ।।17.24।।इसलिये वैदिक सिद्धान्तोंको माननेवाले पुरुषोंकी शास्त्रविधिसे नियत यज्ञ? दान और तपरूप क्रियाएँ सदा इस परमात्माके नामका उच्चारण करके ही आरम्भ होती हैं। Shri Vaishnava Sampradaya - Commentary Lord Krishna elaborates the ontology of OM TAT SAT and how they are interrelated. The words brahma-vadinam are those who follow the injunctions and ordinances of the Vedic scriptures and refers to the three higher varnas or castes beginning with the brahmins or priestly class, ksatriyas the royal and warrior class and vaisyas the merchant class. Yagna or propitiation and worship to the Supreme Lord is performed exclusively by the Vaisnavas and Brahmins. Tapah or austerities is performed by the Vaisnava brahmins and the ksatriyas. Danam or charity is performed by the ksatriyas and vaisyas and is offered to the Vaisnavas and brahmanas to be utilised for the service of the Supreme Lord Krishna or any of His avatars or authorised incarnations and expansions according to vedic scriptures. Thus the relationship between the three higher varnas has been clarified. All prescribed Vedic rituals must be performed exclusively by the Vaisnavas and brahmanas and always commence with the transcendental sound vibration OM. The Vedas begin with OM as well. Thus the eternal connection between OM and the Vedas and OM and yagnas has been demonstrated and firmly established as only in conjunction with the transcendental sound of OM at the commencement are the Vedas recited and the performance of yagnas is bonafide.