Billy Joel wore a bright yellow Star of David on his black suit during an encore at Madison Square Garden.
Monday's performance by "The Piano Man" came more than a week after a rally by neo-Nazis and other groups in Charlottesville, Virginia, ended in deadly violence against counterprotesters.
When asked about Joel's attire, his spokeswoman on Tuesday quoted Edmund Burke: "The only thing necessary for the triumph of evil is for good men to do nothing."
Joel joined with Patti Smith on stage in taking a swipe at President Donald Trump's administration. Photos of fired officials appeared on screen as Smith sang her hit, "Goodbye to You."
Joel's ex-wife Christie Brinkley and their daughter, Alexa Ray Joel, attended the concert. Many of his relatives died in the Holocaust.