Mount Zion - originally meant “The city of David” which was the lower eastern hill of Jerusalem known as ophel (II Chronicles 27:3 & 33:14).  Later when Mount Moriah became the temple hill and the Ark of the Covenant was brought up out of the city of David to the Temple the name was transferred here (I Kings 8:1 & II Chronicles 5:2) and this became “THE ZION”, the most significant of all sacred places to the prophets and others of those centuries. 

"And the Lord will create upon every dwelling place of Mount Zion, and upon her assemblies, a cloud and smoke by day, and the shining of a flaming fire by night for upon all the glory shall be a defense.          ISAIAH 4:5

"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.

 And many people shall go and say, Come ye, and let us go up to the mountain of the LORD, to the house of the God of Jacob; and he will teach us of his ways, and we will walk in his paths: for out of Zion shall go forth the law, and the word of the LORD from Jerusalem." ISAIAH 2:2-3