Śatapatha Brāhmaṇa ("of a hundred paths") 4.6.8.2

4.6.8.2

yā ha dīkṣā sā niṣat | tatsattraṃ tadayanaṃ tatsattrāyaṇamatha yattato yajñasyodṛcaṃ gatvottiṣṭhanti tadutthānaṃ tasmādenānudasthurityāhuriti nu purastādvadanam

The consecration-ceremony, then, is a sitting down, it is a session, it is an (under)going, it is the (under)going of a session. And when afterwards, having reached the end of the sacrifice, they rise, that is 'the rising:' hence they say of them, 'They have risen.' So much, then, for preliminary remark.