ChU 1.11.4
अथ हैनं प्रस्तोतोपससाद । प्रस्तोतर् या देवता प्रस्तावम् अन्वायत्ता तां चेद् अविद्वान् प्रस्तोष्यसि मूर्धा ते विपतिष्यतीति मा भगवान् अवोचत् । कतमा सा देवतेति
atha hainaṃ prastotopasasāda | prastotar yā devatā prastāvam anvāyattā tāṃ ced avidvān prastoṣyasi mūrdhā te vipatiṣyatīti mā bhagavān avocat | katamā sā devateti
Devanagari rendered by HREEM from the edition's roman (IAST) text; the IAST is the edition's own.
Then the Prastotri approached him, saying: 'Sir, you said to me, "Prastotri, if you, without knowing the deity which belongs to the prastâva, are going to sing it, your head will fall off,"—which then is that deity?'
Translated by F. Max Müller