It was quite dangerous for messengers back in the medieval era. They often had to wear mail armor.
The Staring Viking
There was once a Viking who became such a powerful warrior, he decided to take up a new challenge. The Viking sailed across Europe challenging people to staring contests.
He was so confident in his abilities that he promised to hand over all of the gold he had pillaged to anyone who could defeat him. The news spread throughout Europe, catching the attention of a couple in Ireland whose daughter was born without eyelids.
Believing that their daughter was guaranteed to win in a staring contest, the couple sent a messenger to invite the Viking to Ireland to face off against her. He gladly accepted the challenge, setting sail the next day.
The Viking eventually arrived at the couple's home, where he and the daughter had a staring contest which lasted for hours, and eventually days. Nearly a week had passed, and the Viking's eyes remained wide open. At this point, the girl was so exhausted that she decided to forfeit the match, losing by default.
Her parents were baffled. The wife asked her husband, "How could he have kept his eyes open for so long, even against someone with no eyelids?". With no good explanation, the husband shrugged and responded "You can lead a Norse to daughter, but you can't make him blink."