In June of 2004, the Diocese of Phoenix began offering the traditional Latin Mass again after a 40-year hiatus. Bishop Thomas Olmsted fully approved this decision and recognized the need to provide pastoral care to Roman Catholics who desired the older form of the Mass and Sacraments. This was in accordance with the guidance of Pope St. John Paul II and Pope Benedict XVI. In 2005, Bishop Olmsted invited the Priestly Fraternity of Saint Peter (FSSP) to administer to these Catholics. Fr. Kenneth Fryar became the first FSSP chaplain and served the community at St. Thomas the Apostle Catholic Church.

The current church property on West Monroe Street in Phoenix was secured by Fr. Joseph Terra, the next pastor, to meet the needs of the growing Mater Misericordiae community. The parishioners were grateful to Bishop Olmsted and the FSSP for their pastoral care. Today, the Mater Misericordiae Parish is led by Fr. Passo, FSSP, and has continued to flourish. In 2021, the parish acquired and reopened St. Edward the Confessor in Phoenix to address the needs of growth. Over the past few years, the parish has been blessed with at least 5 priestly vocations, with four already being ordained as FSSP priests and others to follow. Please remember our vocations in your prayers.