How can sunlight damage your eyes?
The sunlight will burn the retina and cause permanent damage and scaring.
The lens in the eye will focus and intensify the sunlight onto the retina. The sun is an intense energy source. This intense energy will burn and scar the retina from the intense heat. This is no different than what happens when you take a magnifying glass and focus the sun's image on a piece of paper. The heat is intense enough to burn and ignite the paper.