Baruch goes to the ruins of the Holy of Holies and sits there weeping because “that of which we were proud has become dust” (chapter 35). He falls asleep and has a vision (chapter 36-37). In this vision he sees a forest surrounded by a high mountains and rugged rocks. A fountain appears in the forest and uproots the forest and even made the top of the mountain low. All which remained was a single cedar which was finally cast down. A vine arrives when the fountain is peaceful and tranquil, and finds the cedar.
The vine speaks to the tree and tells the fallen tree the forest was destroyed because of its sin. All the cedar ever did was wickedness, never goodness. The cedar is burned to ash while the vine grows and becomes a valley full of unfading flowers. He prays for enlightenment so that he can understand the vision (chapter 38) and the Lord answers him (chapters 39-40). Israel is a vine frequently, see Isaiah 5, for example. This imagery is used in the rabbinic literature, see Sipre Deut. §312 (on Deut 32:9) and W. G. Braude and I. Kapstein, Tanna debe Eliyyahu: The Lore of the School of Elijah (Philadelphia: Jewish Publication Society, 1981) 369. For both these references, see Craig A. Evans, Mark 8:27-16:20 (Dallas, Word, 2001), 220.
Zion is the forest and it will be destroyed and rebuilt after some time. It will then be destroyed again, four times in all. The last kingdom will be the harshest and will exalt itself above the cedars of Lebanon. After the last kingdom the Anointed One will come (the vine, in the vision). This is roughly parallel to the four kingdoms scheme of Daniel 2 and 7, although the writer here does not detail who the kingdoms are who will overtake Zion. The last ruler of the final kingdom will be captured and brought to Mount Zion where the Anointed One will convict him of his wicked deeds and kill him. The dominion of the Anointed One will “last forever until this world of corruption has ended” (40:3).
Baruch asks the Lord about the timing of the events of his vision (chapter 41). He is concerned because many in the nation have “cast away the law.” What will happen to those Jews who are not prepared for this judgment? The Lord’s response (chapter 42-43) concerns those who have “withdrawn” and “mingled with the nations.” The writer seems to have in mind both natural Jews and converts to Judaism who “mingle.” They will be considered as the mountains in the vision, who were “brought low,” and “corruption will take away those who belong to it.” Baruch reports this vision to the people (chapter 44-47).
He tells them the judgment on Jerusalem was just and fair and that the people ought to dedicate themselves to the Law (44:6-7). The ones who will inherit the peaceful time in the future are those who are prepared for it (44:13-14), they have “not withdrawn from mercy and they have preserved the truth of the Law. For the coming world will be given to these, but the habitation of the others will be in the fire” (44:15).
This vision and interpretation is remarkably important for New Testament studies since it clearly shows an expectation of a Messiah who will free Zion from the oppressive last kingdom and establish a peaceful kingdom on earth for a period of time. If this expectation persisted after the fall of Jerusalem when Baruch was written, it most likely was common a generation before when Jesus was active in Galilee. For at least some Jews in the twenties and thirties Rome was oppressive and they did look forward to an Anointed One who will deliver them. Many of the themes present in Baruch could go back at least to the turn of the era.
Since context of this vision the fall of Jerusalem on A.D. 70, the final enemy must be Rome. Jews living in the post-70 world would have longed for God to act justly and punish Rome for destroying the Temple. Baruch makes it clear that the punishment received was just and fair (the cedar in the vision), but also that a restoration of the Temple (and Jerusalem) is God’s plan.