The Book of Joshua and the Twelve Tribes

Under close examination, the Book of Joshua seems to be a precursor to the book of Revelation: another Yehoshua, as commander-in-chief, will dispossess the planet Earth of its usurpers - first sending in two witnesses, then with a series of judgments of sevens, finally defeating the kings with signs in the sun and moon while the kings of the earth all hide in caves. What does the name "Joshua" mean?