Śatapatha Brāhmaṇa ("of a hundred paths") 4.6.6.8

4.6.6.8

atha maitrāvaruṇo japati | prasūtaṃ devena savitrā juṣṭam mitrāvaruṇābhyāmiti tatsavitāram prasavāyopadhāvati sa hi devānām prasavitā juṣṭam mitrāvaruṇābhyāmiti mitrāvaruṇau vai maitrāvaruṇasya devate tadye eva maitrāvaruṇasya devate tābhyāmevaitatprāha tasmādāha juṣṭam mitrāvaruṇābhyāmiti

The Maitrâvaruna then mutters, 'Impelled by the divine Savitri, acceptable to Mitra and Varuna!' Therewith he hastes to Savitri for his impulsion, for he is the impeller of the gods; and 'acceptable to Mitra and Varuna' he says, because Mitra and Varuna are the deities of the Maitrâvaruna (Prasâstri),--thus he announces it to those who are the deities of the Maitrâvaruna: therefore he says, 'acceptable to Mitra and Varuna.'