Joel spent a summer as a youth leader with Noam, the Masorti youth movement.
Joel’s father Daniel Fishel told the JC: “Joel and I belonged to New North London Synagogue in Finchley and Joel was very involved, as a madrich, in Noam for several years.
“He's proud of his Jewish roots and all the strong friendships he's made along the way, through the community and thanks to Rabbi Wittenberg, of course.”
He met Jack after being accepted to study mathematics at Oxford. Both were members of Out of the Blue, the all-male a cappella group associated with the university.
They impressed X Factor judges with their Ed Sheeran mash-up when the hit music show returned this autumn.
After a public vote held this week Jack and Joel won of the four coveted spots for a live performance on this Sunday's show.
Daniel Fishel urged everyone to watch on TV tonight.
“We'd love to feel everyone's continuing support. There's only about a twelve-minute window in which to vote so please have your phones on your laps whilst watching tonight,” he said.
Simon Cowell, Nicole Scherzinger, Louis Walsh and Sharon Osbourne are the judges in the competition, which airs on Saturday and Sunday nights on ITV.
Jack and Joel appear on tonight’s X Factor at 7pm on ITV
