Was worship of 3 times mentioned in Rig Veda III.4.2, a precursor to performing of Sandhyavandana 3 times a day?

Question

Rig Veda III.4.2, dedicated to Āprīs, says as follows:

यं देवासस्त्रिरहन्नायजन्ते दिवे-दिवे वरुणो मित्रो अग्निः | सेमं यज्ञं मधुमन्तं कर्धी नस्तनूनपाद घर्तयोनिं विधन्तम ||

yaṃ devāsastrirahannāyajante dive-dive varuṇo mitro aghniḥ | semaṃ yajñaṃ madhumantaṃ kṛdhī nastanūnapād ghṛtayoniṃ vidhantam ||

Tanūnapāt whom the deities - MITRA, VARUNA and AGNI, worship daily thrice a day, render this our sacred rain-engendering sacrifice productive of water.

The translation is of H.H. Wilson.

---

tanun indicates the wind or vAyu

napāt indicates grand son or descendant

So it might indicate grandson or descendant of vAyu.

---

My questions are:

1. Who is the Tanūnapāt whom the deities - MITRA, VARUNA and AGNI, worship daily thrice a day?

2. Was worship of 3 times mentioned in this mantra, a precursor to performing of Sandhyavandana 3 times a day?

Answer 1

1. In Bṛhaddevatā (page.77), it was mentioned that Agni is also called as Tanūnapāt

2. Sandhyavandanam was used to be done 2 times a day, as sandhya - twilight time occurs twice daily. Subsequently, another time at midday was added at a later date.