For the hand of the Lord will rest on this mountain.
The first and last phrases of today’s First Reading are identical: “on this mountain”. The First Reading is taken from the twenty-fifth chapter of Isaiah, and “this mountain” that the Advent prophet describes bears a two-fold meaning. “This mountain” refers to the earthly reign of the Messiah, and also to His heavenly Kingdom.
A mountain is a fitting place for the earthly Messiah to bestow His blessings. After all, as we hear in Isaiah 11, the Messiah is “set up as a signal for the nations”, which the “Gentiles shall seek out”. What better place for a signal to the nations than a mountaintop? The higher the mountaintop, the farther away it can be seen.
The second meaning of “this mountain” is the Messiah’s kingdom in Heaven. When a human person looks up at the night sky, he can—weather permitting—see the moon and other “heavenly bodies”. These same objects in “the heavens” can be seen simultaneously by persons at very distant points upon the earth. An example of this would be the Christmas narrative of the wise men travelling to Bethlehem by the light of a star.
All the more, though, is eternal Truth a lodestar for mankind. Truth abides not in any “heavens” seen from the vantage point of earth. Truth abides in Heaven itself, and from that eternal Heaven God the Father sent His Son—who is the Truth—to become man in order to proclaim the Truth in words and works. The divine person of Jesus speaks and acts to redeem fallen man and to lead him to the eternal Heaven.