The relic is believed by Catholics to be a splinter of wood from the cross on which Jesus was crucified.

Terry Donilon, a spokesman for the Archdiocese of Boston, said the true cross was discovered in the fourth century and since then its particles have been distributed to the Church throughout the world.

"The relic of the true Cross is an important sacramental that helps Christians contemplate the crucified Savior and the great suffering he endured for the salvation of the world," Donilon said.

"In the Christian faith, the Cross of Christ is an expression of the triumph of Christ over the powers of darkness."

Father Gaspar also commented on the theological significance of the relic.

"The cross is the sign of God's love for the world. On the wood of the cross, Christ shed his blood to take away our sins," Father Gaspar said.

"The faithful, when we come into contact with a relic that we believe to be a piece of that true cross, are reminded of an event that took place in history. The crucifixion changed the whole course of human history," he added.

The cathedral's relic of the true cross was brought from France in the 1800's, a gift from the cathedral's first pastor, Father Abbe de la Poterie.

Father de la Poterie was a French priest who celebrated the first public Mass in Boston on Nov. 2, 1788, a time when Catholics were a minority in Boston, according to Father Gaspar.

"The real sorrow for us in the archdiocese is that in addition to the spiritual significance and value of this sacred relic, there is also an historical significance," Father Gaspar said.

Meanwhile, saddened Cathedral parishioners have been praying for the relic's return.

"There's also a sense of violation," Father Gaspar said. "All Catholics in general feel violated. We take for granted our sanctuaries are safe places."

"To think someone could come in and vandalize or destroy our sacred space brings a tremendous sense of sadness that someone would destroy a sacred space," Father Gaspar continued.