A Frisco priest accused of raping a nun 20 years ago resigned from his parish Sunday. Monsignor Ernesto C. Villaroya of St. Francis of Assisi Catholic Church resigned through a letter that was read aloud during Sunday Masses, church officials said. Mr. Villaroya could not be reached for comment. "Because of the situation which has developed, he feels in conscience that he needs to remove himself from St. Francis of Assisi parish in Frisco," Bishop Charles Grahmann said in a statement that was posted Sunday on the Texas Catholic Web site, adding that he had visited with the priest. "He has asked for an extended leave of absence to think and pray about this experience," Bishop Grahmann said. "His request has been granted."