When Pope Francis addresses a joint meeting of Congress, he'll speak from the same podium where Father Patrick Conroy, chaplain of the House of Representatives, delivers the opening prayer each morning. Father Pat joins Gwen Ifill to reflect on the pope's visit and his own role as a spiritual resource for a polarized group of lawmakers.

Congress passed the USA Freedom Act which overhauls the way U.S. intelligence agencies can monitor phone records. Meanwhile, nearly 4 million federal government had personal information stolen in a widespread attack U.S. officials are blaming on China. On the 2016 campaign trail, four new candidates threw their hats in the ring this week.

After weeks of marathon talks in Switzerland, world leaders reached a preliminary agreement on the future shape of Iran's nuclear program. Indira Lakshmanan of Bloomberg News just returned from the talks and debriefs on the terms of the deal that include limitations on Iran's nuclear capabilities and a lifting of economic sanctions.

After the uproar over Indiana’s Religious Freedom act, lawmakers in that state and Arkansas worked to revise or create new legislation to prove the laws do not allow discrimination. Gwen Ifill talks to Pastor Tim Overton of Halteman Village Baptist Church, Micheline Maynard of Arizona State University and Ron Brownstein of National Journal about the crossroads of business, religion and politics.

In remarks for Christmas before the Roman Curia, Pope Francis delivered a scathing review of the behavior of Vatican officials, decrying the "spiritual Alzheimers" that makes them forget their real purpose. Gwen Ifill talks to Kevin Eckstrom of the Religion News Service about the pope’s latest effort at spurring reform in the Catholic church.

The revelation that the Catholic Archdiocese of Chicago hid decades of child sex abuse was revealed through documents as part of a settlement with victims. The papers describe how church leadership reassigned priests accused of abuse to different parishes. Gwen Ifill talks to Jeff Anderson, attorney for the plaintiffs.

A United Nations panel has sharply critiqued how the Vatican responded to widespread sexual abuse by Catholic priests, which the Vatican calls distorted and unfair. Rev. Thomas Rosica of the Catholic Salt and Light Television Network and Katherine Gallagher of the Center for Constitutional Rights join Gwen Ifill to offer different views on the report.

With public opinion ratings “the envy of every politician in Washington,” Pope Francis received President Obama at the Vatican for an hour-long visit. Gwen Ifill talks to Rev. Thomas Reese of the National Catholic Reporter and Stephen Schneck of the Catholic University of America to make sense of the meeting and assess what unites the pontiff and the president.

Four significant Supreme Court decisions this week including suspects' rights & abortion clinic protests, incumbent Sen. Thad Cochran of Mississippi survives a strong tea-party challenge, and a first person account on the worsening situation in Iraq.   Joining Gwen: Pete Williams, NBC News; Joan Biskupic, Reuters; Martha Raddatz, ABC News; Dan Balz, Washington Post.