Throughout the book of the prophet Isaiah, there are references to God’s holy mountain. In the twenty-fifth chapter of Isaiah, we have still another reference to the holy mountain, and this is our first reading for the weekend. The mountain in question is, of course, Mt. Zion—which is to say, the mountain where the temple of the Lord is situated. The temple is the place where Israel comes together in right praise of God. Now, Isaiah is indeed talking about the Mt. Zion and the Temple that existed in his time, but it’s eminently clear from the language of his prophecy that he is also talking about the mystical Mt. Zion, the definitive temple, the place where the right praise of God has come to full expression.
Bishop Barron’s Sunday Sermons - Catholic Preaching and Homilies