WASHINGTON – Joe Biden’s first stop Wednesday morning before becoming president was a Mass at the Cathedral of St. Matthew the Apostle, one of the most prominent Catholic churches in Washington, D.C.

Biden, just the second Catholic to become president of the United States, is deeply religious and attends Mass every Sunday, referring to his faith as “all about hope and purpose and strength.”

Though he supports abortion and other actions that go against church doctrine, Biden has said his Catholic faith has given him hope during the darkest times in his life, especially after his wife and young daughter were killed in a car crash just days before he became a U.S. senator in 1973.

“Faith sees best in the dark,” he said in a campaign ad last year.

St. Matthew’s, less than a mile away from the White House, is the seat of the archdiocese of Washington and important symbol of Catholicism in American political life.

The funerals for President John F. Kennedy, the nation’s first Catholic president, and Supreme Court Chief Justice William H. Rehnquist were held there. In 2015, Pope Francis delivered a homily there during his trip to Washington. When he was vice president, Biden would sometimes quietly drop in for Mass.

Biden arrived there Wednesday just before 9 a.m. with his wife, Jill, the flashing lights of police and security vehicles illuminating a cold morning. Inside, they were met by Congressional leaders, including Senate Majority Leader Mitch McConnell, House Speaker Nancy Pelosi and Sen. Charles Schumer.

Soon-to-be Vice President Kamala Harris and her husband, Doug Emhoff, also attended.

The Rev. Kevin O’Brien, the president of Santa Clara University, delivered the homily.

“Let all of us hear the good news today: The Lord is near, so no need to worry or to be afraid,” O’Brien said. “One of the surest signs of God’s nearness to us are the people whom God sends our way.”

O’Brien also offered a reminder of “the Lord’s promise, so beautifully proclaimed in the second reading from Paul’s letter to the Philippians (chapter 4, verses 4-9): ‘The Lord is near. Have no anxiety at all, but in everything, by prayer and petition, with thanksgiving, make your requests known to God. ... Then the God of peace will be with you.”

Sean Riley, a 39-year-old flight attendant and parishioner at St. Matthew’s, waited early in the morning to get into the service.

“I’m honored and excited,” Riley said. “I can’t wait to be a part of history.”

The Washington Post’s Hannah Natanson contributed to this report.