Parishioners gather for Mass at the Church of the Immaculate Conception Sunday, March 17, 2019.

PORTLAND, ME - MARCH 17: The Diocese of Portland kicks off a year-long celebration of the Church of the Immaculate Conception's 150th anniversary. (Staff photo by Jill Brady/Staff Photographer.)

Parishioners prepare for Mass at the Church of the Immaculate Conception.

A candle is lit prior to Mass Sunday, March 17, 2019.

The Diocese of Portland kicks off a year-long celebration of the Church of the Immaculate Conception's 150th anniversary.

Bishop Robert Deeley enters the Church of the Immaculate Conception for Mass.

The Diocese of Portland kicks off a year-long celebration of the Church of the Immaculate Conception's 150th anniversary.

The Roman Catholic Diocese of Portland next Sunday will kick off a months-long celebration of the Church of the Immaculate Conception's 150th anniversary.