Verse 3.11.2

न वै तत्र न निम्लोच नोदियाय कदाचन ।
देवास्तेनाहंसत्येन मा विराधिषि ब्रह्मणेति ॥ ३.११.२ ॥

na vai tatra na nimloca nodiyāya kadācana |
devāstenāhaṃsatyena mā virādhiṣi brahmaṇeti || 3.11.2 ||

2. [In answer to a question]—No, indeed, in Brahmaloka the sun never rose, nor did it ever set. O gods, [listen and bear witness to me]. What I am saying is true, and by it may I have no hindrance to my realization of Brahman.

Word-for-word explanation:

[You ask about the sunrise and sunset in Brahmaloka]—na vai, no indeed; tatra, there [in Brahmaloka]; kadācana na nimloca, [the sun] never set; na udiyāya, nor did it rise; devāḥ, O gods [listen to me]; tena satyena, by this which is true; aham brahmaṇā mā virādhiṣi, may I not have any hindrance to my realization of Brahman.

Commentary:

This is an assertion that there is no day or night in Brahmaloka. When a person makes a statement like this, he invokes the gods to bear witness to what he is saying. He is confident that what he is saying is true and that it will be no bar to his being one with Brahman.