Prakaraṇa 3 · Verse 27

यथा नभसि तडिद् विद्युद् आत्मानं दृश्यते क्वचित्

yathā nabhasi taḍid vidyud ātmānaṃ dṛśyate kvacit

Like lightning in the sky, the Self sees itself somewhere

The image of lightning (vidyut) in the sky (nabhas) captures the nature of ātma-darśana