Bernie Sanders, who calls himself a "not particularly religious" Jew, is the only major candidate running for president who isn't a Christian. But in many ways, Sanders is the most Christian candidate in the race.

Of course, I don't mean that Sanders subscribes to Christian ideas about faith and salvation, or even believes that Jesus of Nazareth was anything more than a famous itinerant preacher. In that sense, he is clearly less Christian than any of his rivals. Hillary Clinton is a Methodist, Donald Trump a Presbyterian, and John Kasich an American Anglican who grew up Catholic. Ted Cruz is a Southern Baptist.

But when it comes to the Christian imperative of helping the poor and the sick and the needy — all fundamental elements of Jesus' preaching — Sanders, more than anyone in the race, speaks about government having a moral obligation to help those in need. In promoting the deeply Christian principles that are actually germane to governing a country, Sanders is talking the Jesus talk better than his Christian rivals.

Indeed, if the proudly greedy Donald Trump is the Gordon Gekko in the 2016 race, Bernie Sanders might just be the Pope Francis candidate.

Sanders actually invites the comparison, name-checking the pope in speeches and social media posts. "I think the Vatican has been aware of the fact that, in many respects, the pope's views and and my views are very much related," he told The Washington Post. "He has talked in an almost unprecedented way about the need to address income and wealth inequality, poverty, and to combat the greed that we're seeing all over this world, which is doing so much harm to so many people."

Sanders also invoked Pope Francis and his idea of a "moral economy" when accusing major banks of "destroying the fabric of America." In his infamous interview with the New York Daily News, he explained:

If you are a corporation and the only damn thing you are concerned about is your profits.... that is destroying the moral fabric of this country. That is saying that I don't care that the workers here have worked for decades. It doesn't matter to me. The only thing that matters is that I can make a little bit more money. That the dollar is all that is almighty. And I think that is the moral fabric. To me, what moral is, I've got to be concerned about you. You've got to be concerned about my wife. That's moral to me. That's what I believe in. [Sanders, to the New York Daily News]

Sanders warns about climate change in biblical terms, too, bringing it up more frequently and more forcefully than Hillary Clinton, the only other candidate who publicly believes global warming is real and human-influenced. When Sanders visits the Vatican this week, he plans to bring up "the planetary crisis of climate change and the moral imperative to make sure we leave this planet in a way that is healthy and habitable for future generations."

The pope explicitly links greed and climate change and helping the poor in his encyclical Laudato Sí, hitting the Sanders trifecta. He also explicitly calls on governments to actively work to save the Earth. In his newest document, Amoris Laetitia, Francis calls for government policies that help families ensure "adequate health care" and "find dignified employment."

But what does Sanders actually believe in? He's gotten that question a lot, but in a typical answer in an MSNBC town hall, Sanders said he believes in the Golden Rule: Do unto others as you wish others would do unto you. That is a line straight out of the Bible (Luke 6:31), though Sanders is careful to couch it as a universally recognized tenet of all major religions. This may seem like a sop to religiously unaffiliated millennials or, like Jay Michaelson suggests at The Daily Beast, a calculated bid to make his agnostic "secular Jewish morality" palatable to an electorate that tends to shun atheists.

In a Christian religious tradition that emphasizes works of mercy as well as faith, though, Sanders is batting at least .500. "Not everyone who says to Me, 'Lord, Lord,' will enter the kingdom of heaven," Matthew quotes Jesus as telling his Jewish followers (7:21), "but he who does the will of My Father who is in heaven will enter." (Read Christian blogger Glennon Doyle Melton for more on this.)

Sanders and Francis certainly have their differences. Sanders is running to be leader of a large secular democracy with the world's dominant economy and even more dominant military. Pope Francis is monarch of a tiny nation-state nestled inside Rome and spiritual leader of 1.2 billion Catholics. The pope doesn't have much to say about breaking up too-big-to-fail banks, campaign finance reform, or rebuilding America's crumbling infrastructure, and he and Sanders disagree on some pretty big issues, like abortion and gay marriage. (Also, Francis, like all modern popes, isn't angling to win temporal power; neither did Jesus.)

But when it comes to social justice, the pope and the junior senator from Vermont are kindred spirits.