THE RITUAL or LAY PRIEST
Requirements: Alignment according to deity
Prime Requisite: WIS
Hit Dice: 1d4
Maximum Level: None
Attack Table: as Magic-User
Saving Throws: as Cleric
Weapons & Armor: as Magic-User + religion's holy weapon
Experience Table: as Cleric
Special: Clerical Spells, Divine Intervention, Turn Undead, Magic Items Construction

What is a Priest?: A priest is a servant of a Deity or Higher Power that belongs to an organized religious structure dedicated to promoting its interests on the Material Plane of Existence. The overwhelming majority of them, even bishops, are 0-level characters without one iota of magical power. Most priests are administrators, tutors, scribes or scholars. The rank-and-file is usually not even that, being mostly relegated to performing the mundane tasks necessary to maintain a temple working, from from cooking or washing clothes to being hand servants of the higher-ups.
When a normal person talks of a priest he or she usually means the Liturgical priests that conduct (non-magical) ceremonies and rituals when the faithful visit the temple, conducts marriages, provides counsel and so forth. Ritual priests are something different, they are members of the clergy versed in the inner mysteries of the faith and capable of using true divine magic. This ability requires knowledge that is only obtained within the church or cult, but requires someone who is very special to begin with.
All ritual priests are persons who were born with the same innate supernatural ability of those who become Magic-Users (known as "Second Sight", "The Will", "The Touch", etc in different cultures), but instead of having been trained in the "Science and Art of causing Change to occur in conformity with Will" they recieved tutelage in the art of contacting and drawing power from a particular Higher Entity as well as education in the doctrine they must abide by to remain in that entity's good graces.
These two manifestations of the same supernatural potential are not mutually exclusive, but mastering both divine magic and hemertic sorcery is the province of the likes of Sorcerer-Priests, Temple Wizards and Magicians who make pacts with supernatural entities; all of which are even rarer than spellcasting priests.
Ritual or Lay?: "Ritual Priest" is the official moniker of magic-using priests assigned to a certain temple or location. Many of them chafe under temple life, they know they are special and resent being trapped in one single temple, oftentimes lacking the means for proper divine magical research, and being brought out everytime a mundane wants a wound healed or a curse removed in exchange for gold to fill the church's coffers. They might also dislike having to abide to wishes and orders from the "mundane" superior who rules the temple, usually someone who attain such a position not out of particular piety or special abilities but as most persons rise in most hierarchies: internal politics combined with seniority.
Another factor that tends to sour the temple life for low-ranking ritual priests is their relationship with their hierarchical equals. While non-ritual initiates and acolytes certainly respect the powers commanded by their ritual brothers, they resent the privileged treatment they receive (being exempt from most hard or menial tasks) and the prestige they hold in the temple, and might also envy the special connection they have with the God.
Much to the chagrin of Abbots and High Priests, total obedience to their dictates or even to those of the church as a whole is not a required condition for a ritual priest to be able to use his magical powers. That ability is something dealt solely between the ritual priest and the God. This means a disaffected ritual priest may "flick the finger" at the temple and leave without ill-effect; unless he is abandoning the temple at critical time of great need and keeps to his faith and doctrine the Deity usually pays no heed. Since a temple without ritual priests is nothing but a hot-spot of meaningless ritual, regimentation and theological lore, most temple leaders tend to be extra-nice and accommodating to their ritual underlings, which only makes the resentment and envy issues within the temple worse.
To deal with all these issues, that unattended could lead to mass defections from the church, a long-held tradition allows ritual priests to take wandering sabbaticals with no expiration date. A wandering ritual priest is known as a Lay Priest and over time it became customary that they associate with Templars or Adventuring parties allied (or aligned) with his religion as these groups welcome with open arms someone who has magical healing powers, for obvious reasons.
Letting a ritual priest become a lay priest usually does not prove a total loss for the church. If the priest survives his (mis)adventuers he either eventually tires of adventuring and returns to the fold of the temple, more experienced and powerful, or obtains enough riches and prestige to establish one of his own. Either way his religion will wax in influence and its doctrine will reach other lands and people through the priest's travels.
Place In Church Hierarchy: Although Lay Priests keep the rank they held when they began their travels and rise in rank automatically has they master higher spheres of divine sorcery, they exist partly outside the hierarchy if their church. They cannot give orders to temple priests they "outrank" unless authorized to do so by their temple superior. Templars are technically exempted from obeying a Lay Priest who outranks them, but most do so anyway unless the priest's requests are unfeasible or nonsensical. The same is usually true when a high ranking lay priest visits a small temple with only priests of lower ranks.
As for the authority higher ranking clergy holds over a lay priest the situation is more elastic. Obedience is expected but only mandatory if it benefits the faith or the church as a whole, and it is understood no temple leader may "recruit" a lay priest for extended periods. In the rare instances when it may seem a temple superior is attempting to turn a lay priest into a personal errand boy he usually seeks guidance by prayer before making a decision.
Lay priests are expected to earn their own keep and receive no material or monetary aid from the church. But are allowed to stay at temples temporarily and make use of the facilities as long as they perform tasks in exchange. A lay priest that visits and remains for awhile in temple with no ritual priests can expect a flood of commoners during his stay, all coming to benefit from the healing and blessing capacities of the visitor. The lay priest is expected to accommodate the faithful .

Rules: Except as indicated in the class resume above and the notes below, the Priest class works as Clerics do.
Armor Use: Priests can use the same armor as Magic-Users: none. Unless the campaign permits MUs to use some kind of armor, then the ability should be extended to priests too.
Priestly Regalia (optional rule): In most fantasy art priests' vestments are usually portrayed as some type of simple and very practical toga. Historically, ancient religious ceremonial vestments tended to lean on the opposite direction: elaborate, ostentatious and cumbersome; in some cultures to such extremes that the priest could not move around unassisted. If the GM allows a priest's religious garb could be made of voluminous cloth, with decorated shoulder pads, incrustations, a helmet-like mitre or face-mask, etc. Such robes will grant the priest an AC of 8, equivalent to padded armor. They weight 10 lb but the priest will move as if he had an extra encumbrance level above the total weight carried due to their impractical nature. Appropriate vestments get more expensive as a priest rises in rank, cost for the average variant is level x 50gp, but the vests of the Archbishops and High Hierophants of wealthy cults have been known to be worth thousands of gold pieces.

Tell me why this guy doesn't deserve an AC of 8 when he has two Padded Armors worth of cloth on him
Weapon Use: Priests can use the same weapons as Magic-Users. To list according to LL rules: Hand Axe(*), Dagger, Dart, Sling and Short Sword(*). Priests can also use Quarterstaves even in campaigns where magic-users cannot. If his religion has a holy weapon a priest receives training in it both as a pro-forma and for liturgical ritual purposes and can fight with it at full capacity. If Weapon Mastery rules are in effect a priest cannot have a higher mastery in any weapon than he does for his holy weapon.
* Yes, magic-users can use axes and swords of this kind as they are small weapons. I only realized this as I was writing this article.
Spell Use: Priests gain and use clerical spells exactly as clerics do. It is highly recommended the "extra spells" rules from Wisdom Table II on LL Advanced Edition Companion pg. 6 be applied, even in campaigns that make no other use of that book. This compensates the priest's lessened combat ability compared to the cleric due to limited weapon/armor use and a worse attack table. It bears pointing out that in a campaign that replaces clerics with priests an adventuring party looses its 2nd-best close-combat warrior. Extra clerical spells for high WIS will also allow a priest to have a wider and better selection of healing and support magic, which is the purported role of this class.
Circles of the Mysteries (optional rule): Like clerics, priests learn the full clerical spell list of every spell level they can cast at once, rather than each spell individually. But to represent the wandering nature of lay priests and provide more verisimilitude than simply having a full circle of spells pop into the priest's mind unaided when he attains level 3, 5, 7, etc, a GM can rule each spell level is one of the inner mysteries of the faith that be mastered before every new spell level list is obtained. The lay priest must have the mystery be revealed to him by a lay or ritual priest that can cast that level of spells, or spend a short period of time studying restricted holy books found only within the temple's libraries.
This does not affect the concept of lay priest independence described before. The inner mysteries are a set of knowledge that is widespread, if limited, among the church and can be obtained from multiple sources. If Abbot #1 from temple A does not allow a lay priest to access the holy books in the library or to speak with his ritual priests, Hierophant #2 from temple B certainly will, if only to gain the good graces of a magic-using priest. It is also proper form to perform a service or task for the temple where the lay priest attains higher knowledge of the mysteries as a show of thanks, which provides a great excuse to send the priest and his party on a quest.
Unless a lay priest manages to become such a back sheep that the entire structure of the church, other lay priests included, turn their back on him he will not be barred from acquiring the spell list for higher levels. How one could manage to do without angering his Deity itself and loose all divine magic abilities would be nearly a miracle on its own.
Holy Symbol: A holy religious symbol is a requirement for any use of supernatural priestly powers. To cast spells, turn undead or ask for divine intervention in a ritual a priest must be in physical contact with a holy symbol. if the power they are using is of a projected and directed nature (turn undead, flame strike, etc) the holy symbol must be pointed towards the target.
Many lay priests tattoo the holy symbol of their religion on their chest or on the palms of their hands, to avoid having need of a physical, material holy symbol. The tattoos must be done using inks that have either been Blessed by the 2nd level Cleric spell or mixed with Holy Water.
Holy Weapon: Some religions (not all, or even most) have a weapon associated with their Deity which is considered holy. If this is the case the priest will be trained in it use and can fight with it normally.
For LL religions based on historical examples determining the holy weapon or lack of it is easy: Christianity and Buddhism have no holy weapon (but there are historical examples of the equivalent of Buddhist Templars in medieval Japan, believe it or not). Islam could be ruled by a lenient GM to have the scimitar. Artemis and Apollo have the bow (short only, as Greeks never used longbows), Zeus would have the Javelin, Athena the spear, Thor the hammer, etc. It is possible that the holy weapon of a religion is one the priest class already has access to, Mars' holy weapon is the gladius (short short). In this case no benefits are gained from its use.
Fully fictional deities and religions are a more complex issue. This ability should not be seen as a chance to "weaponize" the priest and nonsensical choices should be ruled out. Deities associated with healing, pacifism and pure knowledge won't have a holy weapon; gods of war, combat, fighting and defensive violence will. Deities based on some concepts might have several choices that would fit nicely, when this happens the choice should go for the most "clerical" weapon. For example: in a Eurocentric campaign the Deity of Justice could have the hammer (the judge's gavel) or the sword (from the statue of goddess Jvsticia) associated with it, in this case the hammer, which is usable by the Cleric class, should be chosen over the sword.
As a final note, there are no known cases of LL Deities with lances, polearms or two-handed swords as their holy weapon, none.
Divine Intervention: Priests can beg for divine intervention in a ritual manner exactly as Templars. The percentage of success is 1% greater than that of an equivalent Templar. When they take part in a divine intervention ritual conducted by someone else the participation of a priest increases the percentile chance by 2% instead of the normal 1% per participant.
A priest which asks for divine intervention to cast a clerical spell when he still has magic memorized will almost certainly suffer divine retribution, except in the most critical circumstances.
Name Level: At 9th level a priest can build a stronghold/church exactly as the cleric can. Temples headed by a former Lay Priest tend to be the ones most stable and with less internecine politicking, because the head of the temple holds the highest authority both in the temporal and magical spheres. Lay priests who remain wanderers after achieving 9th level gets no benefits.
Magic Item Construction: Priests can make magical items after reaching 9th level as described for spell-using classes in Section 8 of Labyrinth Lord. They can make any items a Cleric could with the exception of those that they cannot use, such as armor and certain weapons.
Priests and Laymen: Most religions do not have Templar orders associated with them, there are a few cases of allied deities from the same pantheon who "borrow" templars from the more martial cults within that pantheon but when this is not possible there is still a type of fighting-men that adopts the role Templars would for a particular cult: Laymen.
Laymen are faithful uninitiated mundanes wholly outside a church's hierarchy but have been given basic theology education and the authorization by church authorities to perform certain minor liturgies if a priest is not present, such as leading mass or overseeing a religious festival. Like in the real world Catholic Church laymen come from all walks of life, Fighters can be laymen too all it takes is swearing to serve the interests of the church to their best capacity. The fantasy world being the dangerous place that it is, and most fighters having a taste for wandering and adventure it is common to see them assigned as escorts and companions for travelling priests. Some volunteer outright to accompany a lay priest and become their henchmen requesting only a living stipend in return, their interest is in the rewards for their souls that will be achieved in the afterlife by virtue of faithful service to a holy person.
A lay priest that pays a visit to a major temple of his religion is bound to find a pair or trio of laymen willing to join him. Even in backwater chapels sometimes a fellow that can hold his own in a fight can be encountered. The only game rules difference of laymen is that when serving a priest their Morale and Loyalty are 1 point above that indicated for a normal henchman according to the priest's CHA. Furthermore, two laymen count only as a single henchman for purpose of maximum followers limit.
