What does it mean that the Lord's house will be established in the top of the mountains?
In Old Testament symbolism, a mountain represents a kingdom. So the Lord's house being established in the top of the mountains means the kingdom of the Lord's house—the royal line from David—will be the top kingdom of kingdoms, exalted above smaller kingdoms, and all nations will flow into it.
Les teaches that Isaiah 2:2 speaks of the last days, when the mountain of the Lord's house will be established. He explains that in Old Testament symbolism a mountain means a kingdom. So the kingdom of the Lord's house refers to the royal line coming from David. Being established in the top of the mountains means it will be the top kingdom of the kingdoms, exalted above the hills, which represent smaller kingdoms. All nations will flow into it. Once Israel's Messiah comes and sets up His throne in Jerusalem, the nations will be drawn there like a magnet draws steel.
And it shall come to pass in the last days, that the mountain of the LORD’s house shall be established in the top of the mountains, and shall be exalted above the hills; and all nations shall flow unto it.