"On the princess’ boat was a courtier who, despite the fact that he was accompanied by his wife, was tempted by evil spirits and began to stare at Princess Fevronia with shameful and lustful thoughts. The princess immediately discerned his evil thoughts and exposed them to the man.
Approaching him, she ordered him to scoop up water from the river on one side of the boat and drink it. When the man had done so, she ordered him to go to the other side of the ship and do the same. When the man had drunk the water, Fevronia approached him, and asked: 'Tell me, did you find that the water tastes the same on both sides of the ship, or was it perhaps sweeter on one side than on the other?'
The man answered: 'No, my lady. The water tasted the same on both sides.'
Then she replied: 'And so is the nature of all women. Why then do you want to cheat on your wife, even in thoughts, and think about another woman?'"
[From the Life and Sts Peter and Fevronia]
Unless otherwise specified, the articles here are posted by Father Aleksey, who has no sense of humor and is extremely straight forward.