1- If we have been blindfolded in a dream, it shows a deliberate attempt is being made to deceive us.
If we are blindfolding someone else we are not being honest in our dealings with other people. This may be through ignorance on our part.
2- Psychologically we may need to spend time ‘in retreat’ that is cut off” from visual contact with the external world.
3- In spiritual terms, blindfolding is a rite of Passage. It is a transition between two states.