“the last days.” Isaiah 2:2 is very similar to Micah 4:1 (Isaiah 2:1-4 is very similar to Micah 4:1-5). In this context, the “last days” are the Millennial Kingdom, although at the time Isaiah was writing God had not revealed that there would be a 1,000-year Millennial Kingdom followed by the Everlasting Kingdom, which has a gigantic city that will come down from heaven and land on earth (Rev. 21, 22). Thus Isaiah thought of the “last days” as one everlasting time, the Messianic Age; the kingdom of Christ on earth.
In Isaiah we see how the hope for Christ’s Kingdom on earth was not just a vague idea, but a living hope that burned in the souls of people like Isaiah, and so verses about the hope would pop up seemingly without warning or introduction in all kinds of different contexts. Isaiah had wonderful revelations about the future kingdom of Christ, and because of that, as we see here, he can quickly insert information about it into the text and expect people to understand it. Sadly, as people began to teach and believe erroneous things about the future, such as that when good people die they immediately go to heaven and live there forever, the prophecies of the Millennial Kingdom began to be misunderstood. Today many commentaries written by scholars treat these verses about the future earth as only figurative language instead of taking them literally and using them to build an understanding of what the future life of all the saved people will be—a wonderful life on a restored earth.
Prophecies of the Millennial Kingdom when Christ rules the earth appear throughout Isaiah, sometimes taking up a large number of verses at a time. For example, Isaiah 2:2-4 is about the Millennial Kingdom, as are many other verses in Isaiah (cp. Isa. 1:26; 2:2-4; 4:2-6; 9:3, 4, 5, 7; 11:3-16; 12:1-6; 14:1-2, 30; 16:5; 19:18-25; 25:6-9; 27:6; 28:5-6; 29:17-24; 30:19-26; 32:1-5, 15-20; 33:24; 35:1-10; 41:18-20; 42:4; 44:3-5; 49:8-23; 51:3-6; 54:1-17; 56:4-8; 57:13, 18, 19; 59:19; 60:1-22; 61:4-9, 11; 62:1-12; 65:9, 13-25; 66:10-13, 18-24). This is an impressive list, and the references to the future kingdom of Christ are throughout Isaiah and thus are an example to us about the importance of our future hope and how it should never be far from our mind.
[For more on the coming kingdom of Christ on earth, the Millennial Kingdom, see Appendix 3, “Christ’s Future Kingdom on Earth.” For more on the chronology of the Last Days, see commentary on Matt. 25:32. For more on the terrible death and destruction in the Great Tribulation and Armageddon, see commentary on Dan. 12:1. For more on the first and second resurrection, see commentary on Acts 24:15. For more on people being dead when they die and not alive anywhere in any form, see Appendix 4, “The Dead are Dead”].
“chief.” Not just the highest, but the most important, because the Temple will be on the top, and the city of Jerusalem where Christ will have his palace will be on the south side of the Temple. That Jerusalem and the palace of Christ will be on the south side of Mount Zion is significant because in the biblical culture, “east” was straight ahead and so south was on the right and north was on the left. For Christ to be “on the right hand” of God as the prophecies state, he will have to live and reign south of the Temple where God dwells. Mount Zion will be the highest mountain in the world (Isa. 2:2; Micah 4:1; Ezek. 20:40).
“all nations.” In the future, people from every nation will come to Jerusalem to worship and to be blessed (Ps. 86:9; Isa. 56:6-8; Jer. 3:17; 16:19).
“stream.” The Hebrew word translated “stream” is nahar (#05102 נָהַר), to flow or stream, and it is related to the Hebrew word for “river.” When God is in His Temple in Jerusalem and Christ is reigning as king, the nations won’t just “trickle” into Jerusalem, they will come as a river of people.