Śatapatha Brāhmaṇa ("of a hundred paths") 4.1.3.19

4.1.3.19

athāpagṛhya punarānayati | indravāyū ime sutā upa prayobhirāgatam indravo vāmuśanti hi upayāmagṛhīto 'si vāyava indravāyubhyāṃ tvaiṣa te yoniḥ sajoṣobhyāṃ tveti sādayati sa yadāha sajoṣobhyāṃ tveti yo vai vāyuḥ sa indro ya indraḥ sa vāyustasmādāhaiṣa te yoniḥ sajoṣobhyāṃ tveti

And, having withdrawn (the cup), he again fills it, with (Vâg. S. VII, 8; Rig veda I, 2, 4), 'O Indra and Vâyu, here is Soma-juice: come ye hither for the refreshing draught, the drops long for you!--Thou art taken with a support!--Thee for Vâyu, for Indra and Vâyu!'--with 'This is thy womb: thee for the closely united!' he deposits (the cup). As to why he says, 'Thee for the closely united,'--he who is Vâyu, is Indra; and he who is Indra, is Vâyu: therefore he says, 'This is thy womb: thee for the closely united!'