23:78 (O Mankind) He is the One Who has created for you hearing and sight, and mind (the faculties to perceive and conceive). But, how seldom do you show gratitude by really using them!
When people do not use their faculties , Allah seals their faculties
16:108 Such are those whose hearts, ears and eyes God (His law) has sealed. For, they have remained heedless. [Disuse of faculties brings people down to subhuman levels of existence. 2:171, 7:179]
As a result of it , their hearts become blind
22:46 Have they never journeyed about the earth, letting their hearts gain wisdom, and causing their ears to hear? Indeed, it is not their eyes that become blind, but their hearts that are in the chests become blind.
And with this blindness they claim to see what others cannot see .
20:95 Moses now turned to Saamiri, “What do you have to say O Saamiri?”
20:96 He answered, "I saw what they did not see. So I took a handful (of dust) from the footprint of the Messenger, and cast it away (into the calf). This is what my mind prompted me to do.”