The Greek adjective aphanēs means not manifest, hidden, or unseen. Formed from the negative alpha and phainō (to shine, appear), it literally means not-shining, not-appearing. A hapax legomenon in the New Testament, appearing only in Hebrews 4:13, in a powerful assertion about divine omniscience.
Hebrews 4:13: 'Nothing in all creation is hidden (aphanēs) from God's sight. Everything is uncovered and laid bare before the eyes of him to whom we must give account.' Before God, nothing achieves hiddenness. The all-seeing God is both terrifying to the unrepentant and liberating to the faithful whose suffering goes unseen by people — God sees everything.