The intensity of direct sunlight far exceeds the eye's threshold and can damage the retina. A retina can not be reapired, as I understand. [Somewhat related, I once suffered arc burn on the eye due to uv reflection from a welding operation. It was quite painful. However, as
Grant as stated, uv is very weak during low solar altitudes.]
Following an eclipse, a hospital in England, or was it Scotland, reported a couple of dozen people with eye complaints. IIRC, no permanent damage was found in anyone.
However, at very low solar altitudes (i.e. sunrise and sunset), the additional atmosphere reduces the amount of direct sunlight enough to be "safe", supposedly. Sunset will be safer than sunrise due to the additional dust and moisture raised by heating.
No surprise, observing sunsets is deemed theraputic by some - see
solargazing. This is not something I would recommend.
As for some serious sunset sunspots, the mist from the Thames allowed Thomas Harriot in 1610 to see them, giving us the
first pictoral record known.