It's a tossup between Christmas (Epiphany) or Easter (Feast of the Resurrection)
Christmas - because the Word Became incarnate.
Easter - because by His death on the Cross, the curtain before the Holy of Holies, was "rent asunder" making it possible, for us mere mortals to commune with God Father, through Jesus, the Christ, the Son of God, the New High Priest, by whose death and resurrection our sins have been forgiven.
The three most important feast days in the Catholic Church - in order, top to bottom, are:
1.) Pentecost Sunday - the birthday of the Church.
2.) Easter Sunday - the Resurrection of Our Lord
3.) The Nativity of Our Lord - Christmas
Easter, also known as the Resurrection of Jesus, is considered the most important feast of the Church year by many Christians. It commemorates the central event of the Christian faith - the resurrection of Jesus Christ from the dead. Easter is a time of joy and celebration for Christians around the world.
The three most important feast days in the Catholic Church - in order, top to bottom, are: 1.) Pentecost Sunday - the birthday of the Church. 2.) Easter Sunday - the Resurrection of Our Lord 3.) The Nativity of Our Lord - Christmas
Roman Catholic AnswerThe greatest feast of the liturgical year is Easter, which celebrates Jesus Christ raising from the dead and the completion of His great sacrifice to effect our salvation. The greatest feast is considered to be Pentecost which marks the birth of the Church. Without the descent of the Holy Spirit, the Church would have died out or never really had a start. Easter would follow closely followed by Christmas
If population membership is the sign of importance then it is the Roman Catholic Church.
martin Luther
The single most important religious order of the Catholic Reformation was the Jesuits.
There are many of them around the world. Most important are the ones in Ireland, like St. Patrick's Cathedral in Armagh, the seat of the Catholic Church in Ireland.
Westminster Cathedral.
The most important feast days are called Holy Days of Obligation.
Roman Catholic AnswerThe most important of the sacred signs in the Church are the sacraments.
They either left the Catholic Church of they left the country.
The Catholic Church