"I think the Jewish people put a lot of focus on marrying other Jewish people," Kirshner said. "It's what our survival is really contingent upon. So we know when we struggle with the effects of intermarriage, that we struggle with a whole host of other issues. So for us it's important for Jews to marry other Jews."
Kirshner said there was even a discount.
"There's a Rabbinical discount," he said. "Not unique to me, to any rabbi who wants to do this for their congregation so that they're encouraging their kids or their congregants to meet people who are Jewish."
While JDate may be the most well-known of the dating web sites, Spark's other niche web sites are booming.
"ChristianMingle has probably been one of the sites that's grown faster than any other lately, and I think people are just gravitating back toward values and finding out that marriage is a good thing, long term relationships are a good thing," said Berger.
But Libna Diaz, a devout Christian, said that going to a dating site at first seemed counterintuitive to her faith.
"What kind of tends to happen when you are a person of faith, you're trusting God to just bring this perfect match for you, and I think for some time I was in that mindset where I thought, 'OK, he's just going to drop right out of heaven exactly how I want him,'" said Diaz. "And I came to the realization that my faith without deeds and works is dead."
Tonight, she's getting ready for her date with Marc Tsavaris, whom she met on ChristianMingle.
"When I saw his picture I was like, 'That's a very professional picture,'" Diaz said, laughing. "So I clicked on the profile, and sure enough he's a model by profession. And then just his self-description reflected someone who, number one, is very passionate about their faith like myself, and just wants to love God with all they are."
The two met for dinner.
Tsavaris prayed: "Father God, thank you for bringing us here today, this evening, to celebrate your glory, to celebrate your grace."
Later the couple visited Sabin Howard, a sculptor for whom Tsavaris has posed.
"We need to have him do one of his raps for your video," Howard told "Nightline." "He's such a showman."
"All right," said Tsavaris. "Check it out: 'I turn my back on temptation, / It's time to make a statement, / I don't follow no religion, / What I got, it's based on relations, / Jesus understands what I'm facing, / I talk to him and he's patient, / Plus he knows all the secrets / I got locked up in my basement.'"
"I think there's definitely some chemistry there," said Diaz. "Yeah, absolutely."
"Yeah, certainly," Tsavaris agreed. "We have a very clear connection when it comes to building with the Lord first. But most importantly, when we have conversations about topics that are primary in our lives.
Subscriptions to Spark Networks sites cost from $9.99 to $39.99. And for those who find making connections to be not so easy, Spark Networks offers even more help.
The company maintains call centers where Spark representatives help love-starved subscribers find ways to improve their profiles and dates. The center takes more than 1,700 calls a day.
And if coddling callers isn't enough, Spark also caters to subscribers in person, organizing real-world socials, parties and mixers, and speed-dating events.