The bull, signed by Pope Francis, on the appointment of Grušas will be read out at the start of the Holy Mass.
The pope appointed Grušas after Cardinal Audrys Juozas Bačkis resigned after turning 75, following the Church cannons.
Born in Washington in 1961, Grušas was president of the World Lithuanian Youth Association and a member of the Board of the World Lithuanian Community in the 1990s.
Grušas earned a degree in mathematics and computer science at the University of California at Los Angeles and spent five years working as a technical consultant of marketing for IBM.
He spent a year at the Franciscan University of Steubenville, Ohio, then moved to Rome, where he studied at the Pontifical Beda College, the Pontifical Lithuanian College, and the Pontifical University of St. Thomas Aquinas. He was ordained to priesthood and incardinated for the Archdiocese of Vilnius in 1994.
He earned his bachelor's degree in theology from the University of St. Thomas Aquinas in 1994. Later, he received a license in canon law from the university, and he completed his doctorate there in 2001. Since 2004, he has served as secretary-general of the Lithuanian Bishops' Conference.
