Back in kindergarten, my teacher, a Lubavitcher rebbetzin called Morah Dvorah Shmotkin, taught us a song about Shabbat observance.

It concerned “Big Gedalya Goomber,” a Paul Bunyan-like character whose all-American feats of strength and daring abruptly ended Friday at sunset, since “double double triple pay won’t make me work on Saturday” — or, for that matter, on Friday night.

I don’t know whether Rabbi Dovber Pinson, a Chabad rabbi in Brooklyn, taught the song to former junior middleweight boxing champion Yuri Foreman before ordaining Foreman as a rabbi.

But Foreman learned the lesson the hard way last week, as he lost his bid for the World Boxing Association super welterweight world title in his first-ever Friday night match.

In the Miami match, defending champion Erislandy Lara defeated Foreman, 36, on Friday night. The referee stopped the bout in the fourth round after Lara hit Foreman with a left uppercut to the chin that left Foreman disoriented and unable to continue, according to Boxingnews24.com.

“Being a rabbi, it is sometimes very interesting to mix that with fighting, but Friday night I won’t be in rabbi mode. I will be all fighter,” Foreman told ESPN a day before the fight. “We are going to show skills and heart and power on Friday night.”

Foreman immigrated first to Israel and then to the United States from Belarus. He lives in Brooklyn.

According to ESPN, Foreman was the first Orthodox Jew to win a world title in more than 70 years when he beat Daniel Santos in 2009.