Miller's killing was one in a string of assassinations of priests and religious in the country, including that of Bl. Stanley Rother five months later.
Aware of the danger present to him in Guatemala, in one of his last letters before he died, Miller wrote: "I am personally weary of violence, but I continue to feel a strong commitment to the suffering poor of Central America. …the Church is being persecuted because of its option for the poor."
"Aware of numerous dangers and difficulties, we continue working with faith and hope and trusting in God's Providence. … I pray to God for the grace and strength to serve Him faithfully among the poor and oppressed in Guatemala. I place my life in His Providence. I place my trust in Him."
The date of Miller's beatification has not been announced but is expected to take place sometime in 2019.
In addition to Miller, Pope Francis Nov. 8 declared the martyrdom of Angelo Cuartas Cristobal and eight companions, alumni of the Seminary of Oviedo, Spain, who were killed in Oviedo between 1934-1937; and Mariano Mullerat i Soldevila, a layman and father, who was killed near Arbeca, Spain in 1936.
The pope also recognized miracles attributed to Venerable Edvige Carboni (1880-1952) and Benedetta Bianchi Porro (1936-1964), paving the way for their beatification.
The heroic virtue of nine other Catholics was also declared, advancing their causes along the path of beatification.
They are: Italian Bishop Giovanni Jacono (1873-1957); Filipino Bishop Alfredo Maria Obviar, founder of the Congregation of the Missionary Catechists of St. Teresa of the Child Jesus (1889-1978); Italian Fr. Giovanni Ciresola, founder of the Congregation of the Poor Servants of the Most Precious Blood-Cenacle of Charity (1902-1987); Italian Fr. Luigi Bosio (1909-1994); Italian Fr. Luigi Maria Raineri, member of the Congregation of the Clerics Regular of St. Paul (1895-1918); Spanish Sr. Maria Antonia di Gesu, member of the Discalced Carmelites (1700-1760); Spanish Sr. Arcangela Badosa Cuatrecasas, member of the Congregation of the Sisters of the Blessed Virgin Mary of Mount Carmel (1878-1918); Italian Sr. Maria Addolorata del Sacro Costato of the Congregation of the Sisters of the Passion of Jesus Christ (1920-1954); and Italian Lodovico Coccapani, lay member of the Secular Franciscan Order (1849-1931).