If you're a novice cleric, I strongly recommend the Protection from Evil as your first spell. A lot of young clerics make the mistake of choose the Rejuvenation spell. It's minimum prep is 5, unlike PFE which is 1. Also, casting Rejuve is dependant on dead bodies being around. This is not always the case. While it is not impossible to learn the required magic skills with Rejuvenation, it is more difficult to learn those skills when you have none.
The Basic Cleric Kit
When you start out, it is very easy to go overboard by wanting to keep everything you find that appeals to you. Do not fall into this trap. The more items you have, the heavier you get. The heavier you get, the harder it is for you to be in combat. Encumbrance affects your fighting skills, and you will probably find yourself getting more tired, and have trouble defending against attacks (which is hard enough as it is when you are young)
Keep to the bare essentials, until you reach a point where you can carry more items. Ask yourself, "Do I really need this?"
The Advanced Cleric Kit
Now, below are some of the items that I consider essential for the older cleric. Special Commune Items are to be added as you succeed on each quest. No use carrying them if you do not know the commune yet. Remember, priorities may differ, depending on the type of cleric you are.
There are, of course, more or less items to include, depending on your style. However, it is always a good idea to carry with you a supply of items related to communes.
I also recommend carrying a full herb kit. However, for those who have to battle with burden, jadice flower, yelith root, cebi root and hisan salve is usually sufficient. If you can get your hands on some lujeakave elixir (which helps with nerve damage), that would be good as well.