Śatapatha Brāhmaṇa ("of a hundred paths") 5.4.4.25

5.4.4.25

atheḍāmādadhāti | upahūtāyāmiḍāyāmapa upaspṛśya māhendraṃ grahaṃ gṛhṇāti māhendraṃ grahaṃ gṛhītvā stotramupākaroti taṃ stotrāya pramīvati sa upāvarohati so 'nte stotrasya bhavatyante śastrasya

He then puts the idâ on (the fire). After the invocation of Idâ, he touches water and draws the Mâhendra cup. Having drawn the Mâhendra cup, he sets the chant agoing. He urges him (the Sacrificer) forward to the chant: he gets down (from the throne-seat); he is in attendance at the chant (stotra), in attendance at the recitation (sastra).