There is a newlyweds' cabin on the ship in the sea
The sailors have made two holes in the cabin walls to spy on the newlyweds for their own amusement
The cabin is occupied by a newlywed Protestant priest and his wife, the sailors (a father and his son) are spying on them.
They witness the pastor (who is apparently in need of money) convincing his young wife to prostitute herself to a rich English banker, to which she finally agrees. The pastor and his wife speak a language the sailors don't understand, so it's not clear what is the pastor convincing his wife of till the end of the story.
When the sailors realize what's happening, the father stops watching in disgust and orders his son to do the same