तीर्थवंशोपदेशः
Tīrtha-vaṃśa Upadeśa: Instruction on the Fruits of Sacred Waters
नान्यत्र ब्राह्मणोश्रीयात् पूर्व विप्रेण केतित: । यवीयान् पशुहिंसायां तुल्यधर्मो भवेत् स हि
nānyatra brāhmaṇośrīyāt pūrvaṁ vipreṇa ketitaḥ | yavīyān paśuhiṁsāyāṁ tulyadharmo bhavet sa hi ||
भीष्म उवाच—यदि ब्राह्मणेन पूर्वमेव अन्येन ब्राह्मणेन श्राद्धे निमन्त्रितः स्यात्, तदा स निमन्त्रितो ब्राह्मणो नान्यत्र गत्वा भोजयेत्। यदि तु तथा करोति, स हीनः परिगण्यते, तस्य च दोषः पशुहिंसासमः स्मृतः।
भीष्म उवाच
One must honor a prior śrāddha invitation; breaking it by eating elsewhere is a serious breach of dharma, treated as morally weighty—likened to the sin of animal-slaughter—because it violates trust and disrupts sacred hospitality.
In Anuśāsana Parva, Bhīṣma instructs on righteous conduct and ritual-social duties. Here he lays down a rule for Brahmins regarding invitations for ritual feeding: once invited, the invitee should not accept food elsewhere, and doing so incurs grave fault.