PHILADELPHIA — An order of nuns brought their fight to stop a natural gas pipeline project on their rural Pennsylvania property to a federal appeals court Friday.

The Adorers of the Blood of Christ argue that the construction of a pipeline through their cornfield in Lancaster County represents a violation of their religious freedom and duty to preserve the earth.

A lower court dismissed the nuns’ lawsuit last year, and the pipeline company already has been given permission to use the land to build the Atlantic Sunrise project, which is more than 20 percent finished.

But the sisters, backed by a courtroom full of supporters in Philadelphia, said they’re undeterred.

“If there’s anybody who thinks sisters live quiet, uneventful lives, they have not met the Adorers of the Blood of Christ,” Sister Janet McCann said after the hearing. “And they have not heard about our resistance to the forced placement of a 42-inch high-pressure fracked gas pipeline on our farmland in Lancaster, Pennsylvania.”

Lawyers for the Federal Energy Regulatory Commission and the Transcontinental Gas Pipe Line Company said the order doesn’t have grounds to object because it never brought its religious freedom argument to the federal agency.

“They had the opportunity to present a defense, and they chose not to,” company lawyer Elizabeth U. Witmer told the panel of appeals judges. “They have simply waived all of their rights.”

In a statement, the company reiterated the basis of the lower court’s decision to toss the case because of insufficient evidence that the pipeline will infringe on nuns’ religious beliefs. It said the pipeline will be a good source of inexpensive natural gas.

The Adorers of the Blood of Christ’s legal claim draws, in part, on Pope Francis’s 2015 encyclical letter, Laudato Si, which they said provides a theological basis that members of the Roman Catholic Church and others must protect the earth as god’s creation. A copy of Francis’s letter was attached to one of the nuns’ legal filings.

The nuns also allowed an outside group to build a makeshift chapel on the land.

J. Dwight Yoder, the order’s lawyer, framed the case in religious terms when talking with reporters.

“It’s David versus Goliath,” he said after the hearing. “And we have to believe that there is a way to get this done.”