निष्ठीवने कृते तेषां सवितुः पुरतः स्थिते । शोणितं दृश्यते यस्य तमशुद्धं विनिर्दिशेत्
niṣṭhīvane kṛte teṣāṃ savituḥ purataḥ sthite | śoṇitaṃ dṛśyate yasya tamaśuddhaṃ vinirdiśet
When the spitting rite has been performed, while standing before Savitṛ (the Sun), if blood is seen in someone’s spittle, that person should be declared impure (i.e., not cleared).
Lomaharṣaṇa (Sūta), by Mahēśvarakhaṇḍa context
Tirtha: Savitṛ/Bhaṭṭāditya ordeal-site (implied)
Type: temple
Scene: A tense moment: the subject spits as officiants watch; a small trace of red appears, while the Sun blazes overhead as witness, and the assembly turns solemn.
Dharma traditions sought objective signs under divine witness; the Sun symbolizes impartial seeing in matters of accusation.
This is part of the Bhaṭṭāditya-associated divya practice described in the chapter.
After the spitting rite before the Sun, the appearance of blood is taken as a mark of non-clearance/impurity.