Jaiminīya (Talavakāra) Brāhmaṇa 1.173

1.173

Thus the sacrificer milks the sacrifice.
Immediately after sacrificing, he becomes better off.
It is: 'Yajñā-yajñā vo agnaye...'
This is indeed sacrifice after sacrifice, namely the Yajñāyajñīya.
Because it conveys sacrifice after sacrifice, that is the essence of the Yajñāyajñīya's name.
By means of this, in ancient times, they used to praise all the stotras.
Regarding this they say: 'Upward indeed do they ascend to the heavenly world who sacrifice;
they are liable to fall away beyond.' Therefore they praise with the Yajñāyajñīya at the end.
This [earth] is the Yajñāyajñīya.
Upon this [earth] they firmly establish themselves.
Placing water nearby, they praise—for the Yajñāyajñīya is Agni Vaiśvānara—for its appeasement, that it may not burn.
Between her thighs, the wife rolls [a vessel of water] forward.
Thereby she appeases Agni Vaiśvānara.
Uncovering her thigh, as it were, she rolls it forward.
For having uncovered her thigh, as it were, the wife produces vital power.
They make her look [at it] for the depositing of seed.
Regarding this they say: 'The wife takes away the Udgātṛ's offspring when they make her look while the sāman is being sung.'