Śatapatha Brāhmaṇa ("of a hundred paths") 3.1.4.12

3.1.4.12

ākūtyai prayuje 'gnaye svāheti | ātmanā vā agra ākuvate yajeyeti tamātmana eva prayuṅkte yattanute te asyaite ātmandevate ādhīte bhavata ākūtiśca prayukca

'To the Purpose, to the Impulse, to Agni, hail!' he says; for by his own mind he purposes to sacrifice, and from his own mind he impels it (the sacrifice) when he performs it: these two deities the Purpose and the Impulse--are meditated upon (âdhîta) in his mind.