in the last days: i.e. the days of Messiah.
mountain of the LORD'S house. Psalms 24:3. Compare Psalms 68:15. See note on Ezekiel 28:16. the LORD'S. Jehovah's. App-4.
all nations. Figure of speech Synecdoche (of Genus). many from all nations.
flow. stream. Same word as in Jeremiah 31:12.