Adaradalopah III.3.40 (399)

On account of the respect shown (to the Pranagnihotra by the Sruti) there can be no omission (of this act) (even when the eating of food is omitted).

Adarat: on account of the respect shown; Alopah: there can be no omission.

This Sutra gives the view of the Purvapakshin or the opponent.

Because there is loving emphasis on Pranagnihotra in Jabala Sruti, such Pranagnihotra should not be omitted.

In the Vaisvanara Vidya of the Chhandogya Upanishad, the worshipper is asked first before he takes his meals to offer food to each of the Pranas, saying "To Prana I offer this". The Sruti attaches much importance to this Pranagnihotra. The Sruti enjoins that food must be offered to the Pranas even before entertaining guests.

Now the question is whether the Pranagnihotra is to be observed even on days of fasting.

The Sutra declares that there should be no omission of it even on days of fasting, as the Sruti attaches much importance to it. The Jabala Sruti says it must be observed even on days of fasting by sipping at least a few drops of water.

To this Purvapaksha the next Sutra gives a reply.

Upasthite'tastadvachanat III.3.41 (400)

When eating is taking place (the Pranagnihotra has to be performed) from that (i.e., the food first eaten), for so (the Sruti) declares.

Upasthite: being present, being near, when food is served; Atah: from that, on that account; Tadvachanat: for so (the Sruti) declares.

This Sutra refutes the view expressed in the last Sutra, and declares that Pranagnihotra, need not be performed on fasting days, because the Sruti expressly declares, "Therefore the first food which comes is meant for Homa. And he who offers that first oblation should offer it to Prana, saying Svaha" (Chh. Up. 19.1).

The first portion of the food should be offered to the Pranas on those days when it is taken. The Sruti gives importance to this only and not that it should be observed even on days of fasting.