तीर्थवंशोपदेशः
Tīrtha-vaṃśa Upadeśa: Instruction on the Fruits of Sacred Waters
जातकर्मादिका: सर्वास्त्रिषु वर्णेषु भारत । ब्र्मक्षत्रे हि मन्त्रोक्ता वैश्यस्य च युधिष्ठिर
jātakarmādikāḥ sarvāstrīṣu varṇeṣu bhārata | brahmakṣatre hi mantroktā vaiśyasya ca yudhiṣṭhira ||
Bhishma said: “O Bharata (descendant of Bharata), in the three twice-born social orders the entire set of sacraments—beginning with the birth-rite (jātakarma)—is enjoined. For the Brahmin and the Kshatriya, and likewise for the Vaishya, these rites are to be performed with the recitation of Vedic mantras, O Yudhishthira.”
भीष्म उवाच
Bhishma teaches that the classical life-cycle sacraments (saṃskāras), starting with jātakarma, are prescribed for the three twice-born varṇas—Brahmin, Kshatriya, and Vaishya—and that these rites should be performed with Vedic mantra-recitation, emphasizing ritual propriety as part of dharma.
In the Anushasana Parva’s instruction on dharma, Bhishma continues advising King Yudhishthira about duties and norms. Here he specifies who is entitled/obligated to perform the saṃskāras and how—namely, with mantras—for the three varṇas he lists.