The ethereal barrier is a defense against the passage of extradimensional creatures, including characters or monsters that are phased, ethereal, or travelling via dimension door or shadow walk. The priest creates an imperceptible barrier of 10 square feet per level that may be arranged in any fashion the priest desires. For example, a 3rd-level character can ward six 10-foot by 10-foot surfaces, which would be sufficient to guard a 10-foot by 10-foot by 10-foot room (four walls, a ceiling, and a floor need to be protected.) Note that some monsters may be capable of abandoning their ethereal approach in order to simply enter the barred area on their own feet-the ethereal barrier only bars their passage as long as they are traveling in the Border Ethereal. Also, while this spell can't be worn down by any form of attack, it does not bar teleportation, gates, or the passage of astral creatures.
Ethereal barrier may be cast as cooperative magic by several priests working together. As long as all involved characters can cast the spell, the areas of effect of each priest are added together. Total the levels of all priests involved and multiply by two to find the number of 10-foot by 10-foot squares that may be warded. For example, four 6th-level casters (24 total levels) can ward 48 10-foot by 10-foot squares. The duration is determined by the highest level priest involved, plus 1 turn for each additional priest. In the previous example, this would be 6 turns plus 3 turns for three additional priests for a total of 9 turns.
This spell is also suitable for focus magic (see the spell focus in the Tome of Magic). The material component is a special compound of rare earths and lead worth at least 10 gp per application. One application is required for each 10-foot by 10-foot square to be warded.

By means of this spell, a priest is able to project his astral body into the Astral plane, leaving his physical body and material possessions behind on the Prime Material plane.
As the Astral plane touches upon the first levels of all the outer planes, the priest can travel astrally to the first level of any of these outer planes as he wills. The priest then leaves the Astral plane, forming a body on the plane of existence he has chosen to enter.
It is also possible to travel astrally anywhere in the Prime Material plane by means of the astral spell. However, a second body cannot be formed on the Prime Material plane.
As a general rule, a person astrally projected can be seen only by creatures on the Astral plane. The astral body is connected at all times to the material body by a silvery cord. If the cord is broken, the affected person is killed, astrally and materially, but generally only the psychic wind can cause the cord to break. When a second body is formed on a different plane, the silvery cord remains invisibly attached to the new body.
If the second body or astral form is slain, the cord simply returns to the caster's body where the body rests on the Prime Material plane, reviving it from its state of suspended animation. Although astral projections are able to function on the Astral plane, their actions affect only creatures existing on the Astral plane; a physical body must be materialized on other planes.
The spell lasts until the priest desires to end it, or until it is terminated by some outside means, such as dispel magic spell or destruction of the priest's body on the Prime Material plane--which kills the priest. The priest can project the astral forms of up to seven other creatures with himself by means of the astral spell, providing the creatures are linked in a circle with the priest. These fellow travelers are dependent upon the priest and can be stranded if something happens to the priest. Travel in the Astral plane can be slow or fast, according to the priest's desire. The ultimate destination arrived at is subject to the desire of the priest.