Rig Veda 2.12.1

Sanskrit text [Accents, Plain, Transliterated]:

यो जा॒त ए॒व प्र॑थ॒मो मन॑स्वान्दे॒वो दे॒वान्क्रतु॑ना प॒र्यभू॑षत् । यस्य॒ शुष्मा॒द्रोद॑सी॒ अभ्य॑सेतां नृ॒म्णस्य॑ म॒ह्ना स ज॑नास॒ इन्द्र॑: ॥
यो जात एव प्रथमो मनस्वान्देवो देवान्क्रतुना पर्यभूषत् । यस्य शुष्माद्रोदसी अभ्यसेतां नृम्णस्य मह्ना स जनास इन्द्रः ॥
yo jāta eva prathamo manasvān devo devān kratunā paryabhūṣat | yasya śuṣmād rodasī abhyasetāṃ nṛmṇasya mahnā sa janāsa indraḥ ||

English translation:

“He, who as soon as born,is the first (of the deities); who has done honour to the gods by his exploits; he, at whose might heaven and earth are alarmed, and (who is known) by the greatness of his strength, he, men, is Indra.”

Commentary by Sāyaṇa: Ṛgveda-bhāṣya

Who has done honour to the gods by his exploits: who has preserved or protected them, or has surpassed them: prayarakṣad atyakrāmad iti vā (Nirukta 10.10); Atharvaveda 20.34; he, men, is Indra: sa janāsa Indra = janā, he asurāḥ; the legend: Gṛtsamada,by his devotions, acquired a form as vast as that of Indra, visible at once in heaven, in the firmament, and on earth; the two asuras, Dhuni and Cumuri [Bṛhaddevatā 4.66-67), mistaking him, therefore, for Indra, were proceeding to attack him, when he arrested their advance by repearing this hymn, intimating that he was not Indra; another legend: when Indra and the gods were present at a sacrifice celebrated by Vainya, Gṛtsamada was one of the officiating priests; the asuras came to the spot to kill Indra, who, assuming the likeness of Gṛtsamada, went away without question; when the assembly broke up, and Gṛtsamada went out, the asuras, who had been lying in wait, considered him to be Indra, and were about to fall upon him, when he diverted from their purpose by reciting this hymn, showing that Indra was a different person n; another legend: Indra came alone to the sacrifice of Gṛtsamada, and being, as before away laid by the asuras, asumed the person n of the ṛṣi and coming forth, returned to svarga; after waiting sometime, the asuras entered the chamber of sacrifice, and laid hold of Gṛtasamads, conceving that Indra had assumed his person n until they were person aded of their mistake by the repetition of the entire sūkta (Mahābhārata)

Details:

Ṛṣi (sage/seer): gṛtsamadaḥ śaunakaḥ [gṛtsamada śaunaka];
Devatā (deity/subject-matter): indra:;
Chandas (meter): triṣṭup ;
Svara (tone/note): Swar;

Padapatha [Accents, Plain, Transliterated]:

यः । जा॒तः । ए॒व । प्र॒थ॒मः । मन॑स्वान् । दे॒वः । दे॒वान् । क्रतु॑ना । प॒रि॒ऽअभू॑षत् । यस्य॑ । शुष्मा॑त् । रोद॑सी॒ इति॑ । अभ्य॑सेताम् । नृ॒म्णस्य॑ । म॒ह्ना । सः । ज॒ना॒सः॒ । इन्द्रः॑ ॥
यः । जातः । एव । प्रथमः । मनस्वान् । देवः । देवान् । क्रतुना । परिअभूषत् । यस्य । शुष्मात् । रोदसी इति । अभ्यसेताम् । नृम्णस्य । मह्ना । सः । जनासः । इन्द्रः ॥
yaḥ | jātaḥ | eva | prathamaḥ | manasvān | devaḥ | devān | kratunā | pari-abhūṣat | yasya | śuṣmāt | rodasī iti | abhyasetām | nṛmṇasya | mahnā | saḥ | janāsaḥ | indraḥ

Multi-layer Annotation of the Ṛgveda

[Rigveda 2.12.1 English analysis of grammar]