The Isaiah passage uses the metaphor of a fine banquet to make the prophetic announcement of God’s deliverance and providence for his people. In that sense, it looks forward to a time in the future. The Revelation passage takes us to that future, and we see the Isaiah prophecy fulfilled in the Lamb, meaning Christ. Isaiah’s fine banquet becomes the “wedding banquet of the Lamb” in Revelation – “for the testimony of Jesus is the spirit of prophecy.”