तीर्थवंशोपदेशः
Tīrtha-vaṃśa Upadeśa: Instruction on the Fruits of Sacred Waters
परोच्छिष्टं च यद् भुक्तं परिभुक्त च यद् भवेत् । दैवे पित्रये च सततं त॑ भागं रक्षसां विदु:
bhīṣma uvāca | parocchiṣṭaṃ ca yad bhuktaṃ paribhuktaṃ ca yad bhavet | daive pitrye ca satataṃ taṃ bhāgaṃ rakṣasāṃ viduḥ ||
Bhīṣma said: Food that has become another’s leavings, or from which someone has already eaten, and likewise food that one consumes without first offering the due portions to the gods and to the Pitṛs—such food, in rites for the gods and for the Pitṛs, is always regarded as the share of the rākṣasas.
भीष्म उवाच
One should not use food that is another’s leavings or already eaten-from for divine or ancestral rites, and one should not consume food without first making the proper offerings; otherwise it is deemed spiritually impure and aligned with rākṣasic (harmful, unrighteous) influence.
In the Anuśāsana Parva’s instruction on dharma, Bhīṣma is teaching norms of conduct connected with offerings and purity, explaining which kinds of food are unfit for daiva and pitṛ rites and why such misuse is condemned.