Surah 12. Yusuf, Ayah 84

Lit., "white": i.e., dim with the tears that filled them (Razi). Although Jacob was now deprived of three of his sons, his grief for Joseph was the most acute because he was the only one of the three of whom Jacob did not know whether he was dead or alive.

 Jacob (ﷺ) cried for so long that he became very weak-sighted. Some scholars suggest that he lost his sight completely. This does not contradict Jacob’s beautiful patience because he did not complain to anyone, but expressed his sorrow only to Allah.

The old father's grief is indescribable. Yet with what master-strokes it is described here! One sorrow brings up the memory of another and a greater one. 'Benjamin is now gone! Oh but Joseph! his pretty dream of boyhood! his greatness foretold! and now how dark was the world! If he could but weep! Tears might give relief, and his red and swollen eyes might yet regain their light!' But his grief was too deep for tears. His eyes lost their colour, and became a dull white. The light became a mere blur, a white glimmer. Darkness seemed to cover everything. So it was in the outside world. So was it in his mind. His grief was unshared, unexpressed, and uncomplaining. Who could share it? Who could understand it? He bore his sorrow in silence. Yet his faith was undimmed, and he trimmed the lamp of patience, that sovereign virtue for those who have faith.