Rudra-prasava-varṇana
The Manifestation and Naming of Rudra / Nīlalohita
अतीतानागतं रुद्रं विप्रा ह्याप्याययन्ति यत् / उभे संध्ये ह्युपासीना गृणन्तः सामऋग्यजुः
atītānāgataṃ rudraṃ viprā hyāpyāyayanti yat / ubhe saṃdhye hyupāsīnā gṛṇantaḥ sāmaṛgyajuḥ
The vipras, seated in worship at both twilights, chant the Sāma, Ṛg, and Yajus hymns, thereby satisfying Rudra who spans the past and the yet-to-come.