Pope Leo XIV's coat of arms offers a clear reflection of his Augustinian roots and the values he seeks to promote during his pontificate, particularly unity and communion within the Church.

The shield is divided diagonally into two sections. The upper half features a blue background with a white lily.

The lower half of the shield has a light background and displays an image that recalls the Order of Saint Augustine: a closed book with a heart pierced by an arrow. This is a direct reference to the conversion experience of Saint Augustine himself, who described his personal encounter with God’s Word using the phrase: “Vulnerasti cor meum verbo tuo” - “You have pierced my heart with your Word.”

Pope Leo XIV has also chosen a motto that reflects this Augustinian tradition: In Illo uno unum, which means “In the One, we are one.” The phrase is taken from Saint Augustine’s Exposition on Psalm 127, where he explains that “although we Christians are many, in the one Christ we are one.”

More: https://www.vaticannews.va/en/pope/news/2025-05/pope-leo-xiv-s-motto-and-coat-of-arms.html