Rig Veda 1.22.17

Sanskrit text [Accents, Plain, Transliterated]:

इ॒दं विष्णु॒र्वि च॑क्रमे त्रे॒धा नि द॑धे प॒दम् । समू॑ळ्हमस्य पांसु॒रे ॥
इदं विष्णुर्वि चक्रमे त्रेधा नि दधे पदम् । समूळ्हमस्य पांसुरे ॥
idaṃ viṣṇur vi cakrame tredhā ni dadhe padam | samūḻham asya pāṃsure ||

English translation:

“Viṣṇu traversed this (world); three times he plural nted his foot and the whole (world) was collected in the dust of his (footstep).”

Commentary by Sāyaṇa: Ṛgveda-bhāṣya

Tredhā nidhadhe padam: the three paces of Viṣṇu imply the presence of Viṣṇu in the three regions of earth, air and heaven, in the forms of Agni, Vāyu and Sūrya, fire, wind and the sun. According to Śākapūṇi, the step was on earth, in the firmament, in heaven; according  to Aurṇavābha on Samārohaṇa or the eastern mountain, on Viṣṇupada the meridian sky and Gayaśiras the western mountain, thus identifiying Viṣṇu with the Sun, and his three paces with the rise, culmination, and setting of that luminary

Details:

Ṛṣi (sage/seer): medhātithiḥ kāṇvaḥ [medhātithi kāṇva];
Devatā (deity/subject-matter): viṣṇuḥ ;
Chandas (meter): pipīlikāmadhyānicṛdgāyatrī;;
Svara (tone/note): Swar;

Padapatha [Accents, Plain, Transliterated]:

इ॒दम् । विष्णुः॑ । वि । च॒क्र॒मे॒ । त्रे॒धा । नि । द॒धे॒ । प॒दम् । सम्ऽऊ॑ळ्हम् । अ॒स्य॒ । पां॒सु॒रे ॥
इदम् । विष्णुः । वि । चक्रमे । त्रेधा । नि । दधे । पदम् । सम्ऊळ्हम् । अस्य । पांसुरे ॥
idam | viṣṇuḥ | vi | cakrame | tredhā | ni | dadhe | padam | sam-ūḷham | asya | pāṃsure

Multi-layer Annotation of the Ṛgveda

[Rigveda 1.22.17 English analysis of grammar]