Why Pope Francis Mentioned Dorothy Day and Thomas Merton in His Speech

— -- Two people who are likely going to be Google search terms by the end of the day are Dorothy Day and Thomas Merton.

They were two of the four people Pope Francis highlighted in his historic speech to Congress this morning.

While the other two -- Martin Luther King Jr. and Abraham Lincoln-- are well known, Day and Merton worked slightly more under the radar, even though they are revered figures within the Roman Catholic community.

New Yorker Dorothy Day founded the Catholic Worker Movement and, while many politicians may avoid connection to the word now, she was a Christian socialist.

"Her social activism, her passion for justice and for the cause of the oppressed, were inspired by the Gospel, her faith, and the example of the saints," Pope Francis said during his speech of the Catholic convert who died in 1980 at age 83.

He praised her "tireless work" and called her a "Servant of God."

Thomas Merton was a writer and theologian, having written more than 70 books, many of which were devoted to religious thought.

"He remains a source of spiritual inspiration and a guide for many people," Pope Francis said of the monk who died in 1968 at age 53.

The pontiff went on to quote directly from Merton's autobiography.

"Merton was above all a man of prayer, a thinker who challenged the certitudes of his time and opened new horizons for souls and for the Church. He was also a man of dialogue, a promoter of peace between peoples and religions," the pope said, reiterating one of the major themes of his U.S. trip this week.

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