Light, by definition, is the absence of darkness.
Darkness, by definition, is the absence of light.
This is true in the spiritual realm.
Our imagination and thoughts will have either light or darkness assisting and accompanying them.
There can be no imagining or thinking without either light or darkness being a part. There is no gray area.
In our thoughts and imaginations, we either have an absence of light, which means darkness,
or we have an absence of darkness, which means light.
So, deliberately invite the Light of God to come in your thoughts and imagination all throughout the day.
Consciously be aware of either light or darkness in your inner life.
It will always be one or the other.