Shatapatha Brahmana 3.6.1.25

3.6.1.25

atha laspūjanyā spandyayā prasīvyati | indrasya syūrasītyatha granthiṃ karotīndrasya dhruvo 'sīti nedvyavapadyātā iti prakṛte karmanviṣyati tatho hādhvaryuṃ vā yajamānaṃ vā grāho na vindati tanniṣṭhitamabhimṛśatyaindramasītyaindraṃ hi sadaḥ

Thereupon he sews (the hurdles to the posts) with a needle and cord, with the text (Vâg. S. V, 30), 'Thou art Indra's sewer.' With, 'Thou art Indra's fixed (point),' he then makes a knot, 'lest it should fall asunder.' He undoes it again, when the work is completed; and thus disease befalls not either the Adhvaryu or the Sacrificer. When completed, he touches it (the Sadas) with, 'Thou art Indra's own!' for the Sadas belongs to Indra.