This song takes place at a wedding celebrating a union that is doomed to fail. It's the ultimate setup for snark, with an old man taking a trophy wife on his fourth attempt at marriage.
Costello sings from the perspective of a guest who sees through the charade but resists the urge to express his views - something he would have done in the old days, when he was cruel.
The song is an allegory for Costello's career, which found him writing incisive lyrics taking down many unsavory individuals and institutions. As he got older, however, he became less lyrically belligerent, disappointing some of his longtime fans. "The song is about accepting that there is a perception of you," he said in Rolling Stone. "I started out with all of these furious ideas, and people somehow feel it's a betrayal if you don't represent that all the time. But life is more complicated than that. It's not worth what it takes out of your soul to go back down that road."
Why is this song tagged "No. 2"? Because Costello wrote another (completely different) song called "When I Was Cruel" that was supposed to be the title track for the album, but he replaced it with this one, which he called "When I Was Cruel No. 2." The first song later appeared on his Cruel Smile collection.
Sampling isn't a regular part of Costello's workflow, but on this track he used pieces of "Un Bacio È Troppo Poco," a 1965 song by the Italian singer Mina.
The lyrics for "Mary, Did You Know?" were written by Christian singer and comedian Mark Lowry, after his pastor asked him to write a Christmas musical for their church. Southern gospel musician Buddy Greene later added music to his words.