The altar is the threshold of eternity. – Romano Guardini, Sacred Signs
The altar, on which is effected the Sacrifice of the Cross made present under sacramental signs, is also the table of the Lord to which the People of God is convoked to participate in the Mass, and it is also the center of the thanksgiving that is accomplished through the Eucharist. – General Instruction of the Roman Missal #296
The altar represents the altar of sacrifice and the table of the Lord, where we are invited to share in the gift of His Body and Blood. The Christian altar is the symbol of Christ himself present in the midst of the assembly of His faithful. It is the meeting place of Heaven and Earth.
It is most appropriate for altars to be made of stone because Christ is our Cornerstone.
Gallery of Altars:
Further Reading:
Catechism of the Catholic Church: #1181-1182, 1383, 2570
General Instruction of the Roman Missal #296-308
New Church, New Altar: A Commentary on the Order of Dedication of a Church and an Altar by Paul Turner
Also See:
A Fascinating History of Free-Standing Altars and Masses Facing the People at Notre Dame in Paris: Part 1 Part 2 (PillarCatholic.com)
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