This weekend, Pope Francis is making a landmark journey in the history of the Catholic Church and in the interreligious dialogue among the major monotheistic religions. Traveling to the ruins of the ancient city of Ur, he become the first pope to visit the birthplace of the great patriarch Abraham.

He invited others of the Judaic and Islamic traditions to join him for prayer on the very plains of the revered father of all Jews, Christians, and Muslims. The selection of the place was purposeful and intentional. The pope wanted the interreligious prayer service to be held at Ur. He wanted prayers to be offered at that specific place. Why?

The answer to such a simple question requires some background and explanation.

In the Bible, Abraham comes on the scene at the very beginning of recorded history. He is presented to us after the pre-history portion of the Book Genesis, which is filled with figurative language and relies on the power of symbolism. Abraham concludes that part of salvation history. With Abraham, the Bible enters an historical age. It marks a type of second beginning, not simply by its history but by Abraham’s faith.

In his life, Abraham understands the truth-  proclaimed from the beginning, but not fully realized by God’s people – that God is truly One. There is One God. The witness of Abraham, and its narrative contained in some fourteen chapters of the first book of the Bible, is the story of his strong faith and willingness to do whatever God asked of him.

The account begins by God calling Abraham to leave Ur (which was a type of Jersey City of the ancient world) at the age of 75. The patriarch had relative wealth and comfortability. Although he and his wife were childless, they were surrounded by extended family. The Bible tells us that even after the Great Flood, the human family did not turn back to God. This rebellion culminated in the Tower of Babel and God’s dispersion of humanity into diverse peoples and languages.

Although a descendent of Shem, the eldest son of Noah, it appears Abraham was not raised with a faith in the true God. The rabbinic account of a younger Abraham smashing the idols in his father’s store, however, indicates that – while not formally given to him – Abraham sought to know God and the living God revealed himself to him.

And so, when God called, and gave promises to Abraham, and told him to leave Ur, the patriarch packed up and went. Going through Haran, he started the 1,000 mile journey to the Promised Land. When he arrived, he build altars and monuments to the living God, consecrating the land and designating it as a place of worship.

The ensuing account of Abraham’s life shows some backsliding, but recommitment. It displays a loyalty and affection for God. It describes the birth of his son Ishmael, the spiritual father of all Muslims, and then the birth of his legal first-born Isaac, the spiritual father of all Jews and Christians.

While the Jewish Scriptures and the Koran are similar in their accounts of Abraham,  is the particular event of his sons where the traditions separate. The Koran claims a primacy for Ishmael, while the Bible claims a primacy for Isaac. And this debate is the spiritual reason for the two traditions.

In spite of diverse traditions from the sons of the patriarch, both traditions point back to Abraham and show him immense deference. And so, by understanding this universal love and mutual reverence for Abraham, we have an answer to the question: Why did Pope Francis adamantly want to have prayers offered at Ur?

In choosing Ur, the pope was spiritually calling all monotheistic believers (and all people of goodwill) back home to a purity of faith.

As Pope Francis said in his comments at Ur: “Here, where Abraham our father lived, we seem to have returned home. It was here that Abraham heard God’s call; it was from here that he set out on a journey that would change history. We are the fruits of that call and that journey.”

Pope Francis, therefore, led the world back to the actual place where father Abraham gave that initial “yes” to a faith in the living and true God. It was not a faith in ideology, or power, or any specific nation. It was not a faith of hate or violence.

In truth, the faith of Abraham called him to leave everything he knew and to follow the path that was given to him. It was a “yes” to leave darkness and enter light. It was a choice for truth, goodness, and selfless surrender. It was a “yes” to love and peace.

And it is a “yes” that is much needed among believers today.

Follow Father Jeffrey Kirby on Twitter: @fatherkirby