The president of the United States Conference of Catholic Bishops (USCCB) says Congress has a “once-in-a-generation chance” to pass immigration reform and fix a broken system.

“We cannot let this opportunity pass. Immigration reform would help families, it would help our economy and it would improve our security,” Cardinal Timothy Dolan, New York's archbishop, wrote in an op-ed in the New York Daily News. “Most importantly, it’s the right thing to do.”

The USCCB is a powerful lobbying force on Capitol Hill.

U.S. Catholic bishops, Dolan said, have called for a number of reforms, including a path to citizenship, family reunification, border protection and improvements to refugee protection.

Congress returns from its August recess on Monday and will first face a vote on authorizing military strikes in Syria. Immigration is another issue that’s expected to top this fall’s legislative agenda.

The Senate passed the Gang of Eight’s immigration reform bill in June, 68-32. But, Speaker John BoehnerJohn Andrew BoehnerSpeculation mounts, but Ryan’s job seen as safe Boehner warns Trump: Don't pull out of Korea-US trade deal GOP Rep: Ryan wasting taxpayers dollars by blocking war authorization debate MORE (R-Ohio) has said he won’t take it up in the House.

At a town-hall event in August, Sen. John McCainJohn Sidney McCainSenate's defense authorization would set cyber doctrine Senate Dems hold floor talk-a-thon against latest ObamaCare repeal bill Overnight Defense: Senate passes 0B defense bill | 3,000 US troops heading to Afghanistan | Two more Navy officials fired over ship collisions MORE, (R-Ariz.) said the next few weeks would be a critical time “in the life or death” of immigration reform.

Dolan wrote that the state of immigration in America is a humanitarian problem that can’t be ignored.

“Today, no one can be proud of the enormous underclass of undocumented workers that’s been allowed to form — millions of our neighbors who live on the margins, have their families fractured and are easily exploited,” he wrote.

The immigration system is broken, he added.

“Now’s the time to fix it.”