Erik Sung found inner happiness through a meditation-based religion, but since donating his home near Lake Forest to his church, he said he has experienced anything but peace.

Neighbors are decidedly skeptical about the Maum Meditation Center, which filed a federal lawsuit to force officials to classify it as a religious institution, which is allowed under zoning laws in unincorporated Lake County.

At first, officials questioned whether Sung's two-story, 2,800-square-foot house in a serene, woodsy neighborhood should be considered a community service, like a yoga studio. Officials say they weren't given enough information about the meditation center to declare it a religious institution — until the lawsuit provided more detail.

The case highlights the challenges officials face in legally defining a church without violating the constitutional right to religious freedom — while also accommodating nearby residents.

"All I wanted to do was allow some people to meditate," said Sung, 48, an electrical engineer, who formerly lived alone at the house with his dog. He hopes to stay in the house after it turns into a full-time meditation center, if permitted under the law, much like a priest would live in a rectory.

"We want to be able to bring happiness to everyone else," he said.

In Sung's neighborhood on Elm Road, the driveways are long and winding and the lots large enough that one resident keeps horses on the property. But ever since Sung installed a stone monument that says "Maum" at the foot of his driveway, he said, some have called his faith a "cult" and reported him to authorities for myriad offenses, such as walking his dog without a leash.

Sung, who is footing the bill for improvements to the home, must now meet permit requirements that include adding a parking lot, accessible bathrooms and a sprinkler system. On Thursday, he argued with county inspectors who pointed out the changes required, including moving the stone monument 10 feet away from the property line.

Sung had already obtained permission for the monument, but since it is now considered an advertisement for the church — not art — it must be moved farther away from the street to meet code, said Patrick Tierney, Lake County project manager. The tan stone, placed in the center of a landscaped bed of rocks, sits about 3 feet high with the word "Maum" engraved on the front.

"That thing weighs a ton," said Sung, who also learned he will have to do soil testing and wetland studies before opening the center.

Because of the controversy over the meditation center, a County Board committee is scheduled Tuesday to review its zoning use ordinance and consider restricting the hours for religious assemblies to between 8 a.m. and 8 p.m. Under the proposed amendment, churches would be allowed to assemble up to 15 times annually for events after 8 p.m.

Eric Waggoner, the county's planning and building director, said he did not have enough information about the center when Sung approached officials about his plan in late October.

Frustrated with delays, Sung filed the lawsuit May 22 alleging that his religious freedoms were being violated. Two weeks later, the county agreed that the Maum Meditation Center is a religious institution. Maum will still attempt to recover damages it says are owed by delays in the center's opening. A status hearing is scheduled July 1.

Early on "in the material he presented to us and in discussions with us, the focus was on the physical and psychological benefits of meditation and the description of meditation sessions," Waggoner said. "There wasn't any discussion of the concept of religion."

But he also conceded that there are no hard-and-fast guidelines on what constitutes a religion, and that proposals for new churches are handled on a case-by-case basis.

Legal experts agree that, nationally, administrators and courts have shied away from defining religion.

"No single feature unites all the things that are disputably religions," said Andrew Koppelman, a law professor at Northwestern University and author of the book "Defending American Religious Neutrality."

"For instance, you might think that all religions believe in some god, but then there is Buddhism, which in its original form doesn't care about god at all. All you can say is religions just have a family resemblance to one another."

Despite that, there are very few cases in which courts have struggled to define religion, Koppelman said. "Generally, we know it when we see it."

In Sung's neighborhood, residents who oppose the center in complaints to the county declined to comment. But emails cited in the lawsuit indicate that neighbors are concerned about the number of vehicles at the residence, hours of operation and increased foot traffic.

"You can pick any religion you want, and if they want to build something or change something, people are concerned," Ann Maine, the Lake County board representative for the area, said.

Maum Meditation, "like everybody else, has to follow the process," she said.

In nearby Lake Bluff, officials stopped a man from using the racquetball court in his lakefront mansion as an Armenian church for his family. Village officials said George Michael was trying to avoid paying about $80,000 a year in property taxes.

The Illinois Department of Revenue initially approved the exemption in 2007, but a judge reversed the decision two years later.

Department spokeswoman Susan Hofer said that when determining if an entity is a church, state officials first check if there is an affiliation with an established religious institution. They determine the use of the building, and if it contains a sanctuary or classrooms, a food pantry or child care service.

"Then we look at what the local government says … because they know their neighborhoods," Hofer said.

Maum Meditation, started in South Korea by founder Woo Myung in 1996, claims to operate 340 centers worldwide, according to its website. Members have opened centers in Chicago's Lakeview neighborhood, in Schaumburg and at a temporary site in Glenview.

Practitioners enroll in classes whose fees range depending on the center's need but are typically $150 monthly, said Soonae Yoon, an organizer who ran into resistance while trying to open a center in Morton Grove.

She described the religion as a way to cleanse the mind, discard the ego and achieve truth through an eight-level process.

Five to eight people are expected to meditate together at any one time at Sung's house, with cushioned floor-level seats provided in two rooms. "Helpers" will guide the members through their meditation.

"Maum Meditation is throwing away the false mind," says a sign in one room.