Mahabharata — Anushasana Parva, Shloka 16
अत्रेः तपोबलप्रकाशः तथा च्यवनस्य सोमाधिकारः
Atri’s Illumination by Tapas; Cyavana and Soma-Entitlement
जिसके घर किसीकी मृत्यु हुई हो, उसके यहाँ मरणाशौचके तीसरे दिन अन्न ग्रहण करनेवाला ब्राह्मण बारह दिनोंतक त्रिकाल स्नान करनेसे शुद्ध होता है ।।
dvādaśāhe vyatīte tu kṛtaśauco viśeṣataḥ | brāhmaṇebhyo havir dattvā mucyate tena pāpmanā ||
Bhīṣma said: When the twelve-day period (of impurity observance) has passed, one who has duly completed the rites of purification becomes especially purified. By offering havis (a sanctified oblation/food offering) to Brahmins, he is released from that taint of sin connected with the death-impurity.
भीष्य उवाच
Educational Q&A
After completing the prescribed twelve-day purification connected with death-impurity, one should finalize purification and give a sanctified offering (havis) to Brahmins; this completes the expiatory process and removes the remaining taint.
In Bhīṣma’s instruction on dharma, he outlines the concluding step after a twelve-day observance: special purification and a ritualized gift/feeding of Brahmins with havis, by which the person becomes free from the impurity-associated fault.