The Merchant says that everyone who has a wife, including him, endures much weeping, wailing, and sorrow.
The Merchant describes his wife as a shrew, a woman who could outmatch Satan if she were married to him. The Clerk's story about a patient wife named Grisilde has made him think about the huge difference between Grisilde and his own wife.
If he could do it again, says the Merchant, he would never get married, for married men have great sorrow and trouble, as all wedded men know.
The Merchant tells the Host that he has been married for only two months.
The Merchant says that, even if a wifeless man was stabbed, he could never tell as sad a story as the Merchant can about how awful his wife is.
The Host tells the Merchant to put his money where his mouth is and tell the story already, since he clearly knows so much about it.
The Merchant says he will gladly tell his story, but it's not about his own sorrow in marriage.