Śatapatha Brāhmaṇa ("of a hundred paths") 3.2.1.7

3.2.1.7

sa yadāha | te vāmārabha iti te vām praviśāmītyevaitadāha te mā pātamāsya yajñasyodṛca iti te mā gopāyatamāsya yajñasya saṃsthāyā ityevaitadāha

And when he says, 'I touch you,' he means to say, 'I enter into you.' 'Do ye guard me up to the goal of this sacrifice!' whereby he says, 'Do ye protect me until the completion of this sacrifice!'