(RNS) — Habitat for Humanity was built on a pair of simple yet profound ideas.

Everyone deserves a decent place to live.

Anyone who wants to help make that happen is welcome to pick up a hammer and get to work.

For nearly five decades, those ideas — which Habitat’s founder referred to as the “theology of the hammer” — have helped Habitat grow from its humble beginnings at a Christian commune in Georgia into a worldwide housing nonprofit that’s helped more than 46 million people around the world find a place to call home.

Among those homes are 30 “Unity Build” houses in Nashville, Tennessee, built by an interfaith coalition of congregations over the past three decades. Those congregations believe very different things about God, said Kevin Roberts, a former pastor and director of faith relations and mission integration for Habitat for Humanity of Greater Nashville. But they share a common conviction about helping their neighbors.

That makes a Habitat build site a rare place where people who disagree can work together in polarized times. All they need is a willing pair of hands.

“When you step onto the Habitat build site and someone puts a paintbrush or a hammer or a saw in your hand, no one asks, ‘Who did you vote for?’” said Roberts. “No one asks, ‘Where did you go to church or did you go at all?’”

That inclusive approach has helped Habitat thrive despite the many challenges facing faith-based charities in the United States — including aging supporters in shrinking congregations, a loss of faith in organized religion, and the nation’s growing polarization. 

Jonathan Reckford, CEO of Habitat for Humanity International, said the nonprofit’s mission is to put God’s love in action by providing housing. To do that, he said, requires bringing a wide range of people together. 

Using volunteers to help build a Habitat house is a social change strategy, said Reckford, one that invites people to care about affordable housing and about working with their neighbors. That’s an important task in today’s isolated and polarized times.

“My observation is that when people serve together, they focus on what they have in common,” Reckford said in a phone interview. “They focus on shared values — as opposed to when we sit by ourselves online. Then it’s all about how we are different.”

Reckford hopes to expand that kind of intentional bridge-building in the coming years through a new initiative called Team Up — a partnership of Habitat, Catholic Charities, the YMCA and Interfaith America. The initiative was first announced last fall at a White House summit.

The idea is to address the nation’s divisions by inviting people to build friendships as they serve together to meet community needs. For Habitat, that will likely involve more intentional community building on the worksite and an increased focus on interfaith cooperation.

Reckford said Habitat’s core Christian identity and its commitment to interfaith work go hand in hand. Faith in God is at Habitat’s center — but God is “not a border” to keep others out.

That deep faith, he said, allows Habitat to be “radically inclusive” and to welcome anyone who wants to lend a hand.

“We should not have to give up what has made Habitat successful in order to be joyfully welcoming of others,” he said.

Reckford suspects that community service will become increasingly important for churches and other faith groups in the future, as people become more skeptical of organized religion. Habitat, he said, was born in church basements and grew by tapping into the energy and faith of people who were already church members. Now many churches will have to reach out to people who aren’t part of their community to continue their ministry, he said.

“In our increasingly unchurched culture, community service is going to be the front door for more and more faith communities,” he said. “The first invitation might be ‘Come to serve with me’ rather than ‘Come worship with me.’”