Guarding the Eyes
The Shemen Rokeach teaches that a person who watches over his eyes, making sure they see only holiness, becomes the ruler of his eyes. Hashem gives such a person the power to open his eyes and see whenever he wishes. He said this on the night of his passing, when his sight returned after years of blindness.
Source: Said on the night of his passing, 27 Shevat 5597