The heart is deceitful above all things, and desperately wicked: who can know it?
Jeremiah 17:9
Yes, the consciousness, or heart, of each person is covered, how much depending on the individual, with illusion, darkness, etc.
But that covering of wickedness (and so on) is not the eternal nature of the soul. The eternal nature of the soul is, as a part of the Supreme Soul, God - is to be full of wisdom and happiness.
When the covering (or sometimes compared to a disease) is gradually removed or cured, the natural light of the soul can shine. God is in the heart of every living being. We just have to open up to His presence, and then His light shones in our hearts.