In chapter 7 it is in the first year of the reign of Belshazzar that Daniel had visions in his head upon his bed: and he told Nebuchadnezzar the sum of the matters of this dream. The vision Daniel had represents the day of the Lord, the gospel of Jesus Christ that declares all nations will be saved through judgment which will come upon each man in his own order (1Co 15:23). It is in the first year of Belshazzar’s reign, which represents the day of the Lord, that Daniel is given these powerful dreams of “four great beasts [that] came up from the sea, diverse one from another.”
Then in chapter 8, it is in “the third year of the reign of king Belshazzar” that this next vision comes to Daniel, and as the number reveals, it will be a vision that is centered around the process of judgment [3] that must unfold during the day of the Lord to which Daniel is witnessing, without comprehending the spiritual meaning of these very powerful dreams that caused him to faint and be sick for days (Dan 8:27).
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Here’s the link to the video and audio for this and all the studies thus far with the Book of Daniel: Dan 8:1-27 A vision appeared unto me