tāmaso bhūta-sūkṣmādir
yataḥ khaṁ liṅgam ātmanaḥ
tāmasaḥ - from the mode of passion; bhūta-sūkṣma-ādiḥ - subtle sense objects; yataḥ - from which; kham - the sky; liṅgam - symbolic representation; ātmanaḥ - of the Supreme Soul.
In the Vedic hymns it is said, etasmād ātmanaḥ ākāśaḥ sambhūtaḥ. The sky is the symbolic representation of the Supreme Soul. Those who are egoistic in passion and ignorance cannot conceive of the Personality of Godhead. For them the sky is the symbolic representation of the Supreme Soul.