Why is the astral the fifth dimension

Answers from the books of Samael Aun Weor

The ghosts of the dead live in the fifth dimension; this is ETERNITY. Length, width, and depth are the three dimensions of the cellular world. Time is the fourth dimension; eternity, the fifth dimension, and that which is beyond eternity and time corresponds to the sixth dimension.

In fact, liberation begins in the sixth dimension, the world of the divine spirit; it is the Electronic World of the SIXTH DIMENSION.

Samael Aun Weor. Excerpt from the book: "The Book of the Dead."