Shatapatha Brahmana 9.1.2.1

9.1.2.1

athainamataḥ pariṣiścati | etadvā enaṃ devāḥ śatarudriyeṇa śamayitvāthainametadbhūya evāśamayaṃstathaivainamevametacatarudriyeṇa śamayitvāthainametadbhūya eva śamayati

He then sprinkles him (Agni-Rudra, the fire-altar). For the gods, having now appeased him by the Satarudriya, thereby appeased him still further; and in like manner does this (Sacrificer), now that he has appeased him by the Satarudriya, still further appease him thereby.