When is one wrapped up in & covered by blind Ignorance?
Once a certain not very well-known Bhikkhu asked the Blessed Buddha:
Venerable Sir, ignorance, ignorance, is it said! What is ignorance?
Venerable Sir, in what way is one wrapped up in ignorance?
The Blessed Gotama Buddha then pointed out:
Not Knowing Suffering is ignorance;
Not Knowing The Cause of Suffering is ignorance;
Not Knowing The End of Suffering is ignorance;
Not Knowing The Way to end Suffering is ignorance...
All this absence of understanding is ignorance & it is by that blindness,
that dark state of blocked insight, that one is wrapped up in ignorance!
Therefore, Bhikkhu, an effort should be made much of to understand:
Such is Suffering; an effort should be made much of to comprehend:
Such is the Cause of Suffering; an effort should be made so to realize:
Such is the End of Suffering; An effort should be made to penetrate,
recognize, & develop, Such is the Way leading to the End of Suffering...
More on these 4 Noble Truths (Cattari Ariya Saccani):
http://What-Buddha-Said.net/drops/IV/Clustered_Truths.htm
http://What-Buddha-Said.net/drops/IV/The_Ultimate_Fact.htm
http://What-Buddha-Said.net/drops/II/The_4_Noble_Truths.htm
http://What-Buddha-Said.net/drops/IV/Sour_Sense_Sources.htm
http://What-Buddha-Said.net/drops/II/The_1st_Noble_Truth_on_Suffering.htm
http://What-Buddha-Said.net/drops/II/The_2nd_Noble_Truth_on_The_Cause_of_Suffering.htm
http://What-Buddha-Said.net/drops/II/The_3rd_Noble_Truth_on_The_Ceasing_of_Suffering.htm
http://What-Buddha-Said.net/drops/II/The_4th_Noble_Truth_on_The_Way_to_End_Suffering.htm
What is Ignorance? A Blind Mind!

Source (edited extract):
The Grouped Sayings of the Buddha. Samyutta Nikāya. [V:429]
section 56: Saccasamyutta. Thread 17: Ignorance...