Shiva Purana
यद्यथावस्थितं वस्तु तत्तथैव सदाशिवः ॥ अयत्नेनैव जानाति तस्मात्सर्वज्ञ उच्यते ॥ ४३ ॥
Whatever the object is as it is, so is Lord Sadaśiva. He knows without effort, therefore he is called omniscient.
english translation
yadyathAvasthitaM vastu tattathaiva sadAzivaH ॥ ayatnenaiva jAnAti tasmAtsarvajJa ucyate ॥ 43 ॥
hk transliteration by Sanscript