Shatapatha Brahmana 1.9.2.24

1.9.2.24

tamā vedeḥ saṃstṛṇāti | yoṣā vai vedirvṛṣā vedaḥ paścādvai parītya vṛṣā yoṣāmadhidravati paścādevaināmetatparītya vṛṣṇā vedenādhidrāvayati tasmādā vedeḥ saṃstṛṇāti

(The Hotri) strews it (from the Gârhapatya) as far as (the east end of) the altar; for the altar is female and the veda is male; and from behind the male approaches the female: from behind (i.e. west) he accordingly causes it (the altar) to be approached by that male, the veda. For this reason he strews (the grass of the veda) as far as (the east end of) the altar.