Verse 2.12.2

स य एवमेतद्रथंतरमग्नौ प्रोतं वेद ब्रह्मवर्चस्यन्नादो भवति सर्वमायुरेति ज्योग्जीवति महान्प्रजया पशुभिर्भवति महान्कीर्त्या न प्रत्यङ्ङग्निमाचामेन्न निष्ठीवेत्तद्व्रतम् ॥ २.१२.२ ॥
॥ इति द्वादशः खण्डः ॥

sa ya evametadrathaṃtaramagnau protaṃ veda brahmavarcasyannādo bhavati sarvamāyureti jyogjīvati mahānprajayā paśubhirbhavati mahānkīrtyā na pratyaṅṅagnimācāmenna niṣṭhīvettadvratam || 2.12.2 ||
|| iti dvādaśaḥ khaṇḍaḥ ||

2. He who knows that this Rathantara Sāma is rooted in fire, acquires the kind of glow that Vedic scholarship produces. He also enjoys eating. He lives the full span of his life, and his life is brilliant. He is well known for his children and for his animal wealth, and he commands great respect in society. His vow is that he will never eat with fire in front of him and he will never spit.

Word-for-word explanation:

Saḥ yaḥ evam etat rathantaram agnau protam veda, he who knows that this Rathantara Sāma is rooted in fire; brahmavarcasī, acquires the glow that Vedic knowledge gives; annādaḥ bhavati, he enjoys eating food; sarvam āyuḥ eti, he lives the full span of his life; jyok jīvati, he lives a bright life; mahān prajayā paśubhiḥ bhavati, he distinguishes himself by his children and by the animal wealth he acquires; mahān kīrtyā, his reputation spreads far and wide; tat vratam, his principle is; na pratyak agnim ācāmet, never to

Commentary:

By his moral character and his scholarship in the Vedas, he acquires a radiance about him.

[The underlying thought in these two mantras is that everything a person does is spiritual. This includes even physical experiences.]