These are the secret letters to the Elders in the Jehovah’s Witness congregations from the Watchtower Society. These letters are read only by elders and the vast majority of “regular” Jehovah’s Witnesses have never seen even one of these letters.
The Jehovah’s Witnesses think that communication from the Watchtower Society is “inspired by God” (although the Society has held itself out as a prophet, many regular publishers are not familiar with this claim) and informs the rank and file members of the proper interpretation of the Bible and God’s will.
This over 400 page PDF file will supply the “behind-the-scenes” peek at a very secretive religion. So secretive, in fact, that regular “publishers” (rank-and-file) JWs will be astonished at the level and specificity of the direction given the local Body of Elders (BOE) by the mother organization.