Shatapatha Brahmana 11.4.2.14

11.4.2.14

pārśvata u haike srucamupāvahṛtya hutvā paryāhṛtyopabhṛtyadhinidadhati na tathā kuryādyo hainaṃ tatra brūyādatīrthena nvā ayamadhvaryurāhutīḥ prārautsītsaṃ vā śariṣyate ghuṇirvā bhaviṣyatītīśvaro ha tathaiva syāt

And some, having turned down the spoon sideways, and poured out the oblation, turn it round and place it over the upabhrit. But let him not do so; for if, in that case, any one were to say of him, 'Surely, this Advaryu has stopped the oblations by (following) the wrong way, he (the Sacrificer) will either be shattered, or become worm-eaten,' then that would indeed be likely to come to pass.