The title of the papal document, "Aperuit illis", is taken from Luke's Gospel, where the Evangelist describes how the Risen Jesus appeared to his disciples, and how “he opened their minds to understand the Scriptures”. Francis issued this directive in consequence of his intention to set aside "a Sunday given over entirely to the word of God, so as to appreciate the inexhaustible riches contained in that constant dialogue between the Lord and his people" which he announced at the conclusion of the Extraordinary Year of Mercy, 2015–2016. Francis pays testimony in his letter to Dei verbum, the Second Vatican Council's Dogmatic Constitution on Divine Revelation. The phrase "Dei verbum" is Latin for "Word of God" and is taken from the first line of the document.
