Even the darkness is not dark to You, and the night is as bright as the day. Darkness and light are alike to You. (Psalms 139:12 NASB)
God sees everything and no one can hide from Him. He sees what we do in the dark and in the brightness of day. We cannot hide our deeds done in the dark. What is usually done in the dark is sin, our transgressions, where we think or assume that nobody sees us. The brightness of day does not matter for God to see our obedience to Him and our zeal for holiness. God sees. He has a perfect 20/20 vision to discern even those in the deepest and innermost part of our souls. We may as well keep our thoughts and the intent of our hearts pure and holy.