Preparation of Spells for Arcane and Divine Casters.
 

 Arcane casters must have rested a full uninterrupted 8 hours ( minimum required: full sleep for at lease 6 hours and 2 hours of VERY low activity, no battle or straining activities OR if ELVEN 4 hours of Revere and 4 hours of rest.) to be able to have a clear enough mind that is able to burn into their minds the magical symbols that the sells consist of so that they can release those images upon command. A caster can ONLY memorize his daily allowance per day, example: An Archmage has a daily allowance of say 4 1st level spells per day, so he memorizes 2 magic missiles, a enlarge spell, and a grease spell, throughout his day he fights a battle with several giants and is forced to use his grease spell, and enlarge spell on one of his companions. Then later he is attacked by twin hell hounds and uses a magic missile spell on them. So after this battle this archmage CANNOT sit down a memorize all over again 3 new 1st level spells because his daily allowance is only 4 per day!
 Also to prepare spells for the day the caster must be in a comfortable state (thus inside a burning house would not be a possibility for the caster to memorize his spells at). He must spend a minimum of at least 2 minutes spent in a trance-like state where he is clearing his mind and opening it up to his spells.
  After the meditation then the caster is able to memorize his spells as follows:
It takes 2 minutes per spell level to memorize a spell as long as the spells casting time is a single action. For some spells where the casting time is longer than this (such as spells that take a round to cast or 10 minutes to cast) than it takes 10 minutes per spell level to learn the spell.
 
 

Divine casters are similar in that they must have had the same amount of rest to have clear enough minds to allow their divine magic to enter the temples of their minds. (so see above for description of the rest needed).
A Divine spell caster must elect to learn his/her spells at a certain time each day for the rest of their lives as being a worshipper of their Deity. Some Deities are specific as to when you would learn your magic (example: Lathander is the God of dawn etc so you would elect to memorize spells in the early morning during Dawn. Or in the case of the Goddess of Night or the Moon you would elect to learn your spells at night time. Etc etc) If at this time of day or night the caster doesn’t memorize spells than he or she must wait until the following day to attempt to memorize his or her spells.
 The amount of time it takes in prayer to gain the spells is the same as if the divine caster were an arcane caster.

 The Realms are a very divine orientated world. The Gods are major factors in the life of the living on Toril, their hands in matters of the Realms go mostly unseen, but are there everyday. Such that Mystra watches all the magic that is tapped from the weave (whether it’s a spell, or  the connection between the weave and an enchanted sword or a wand of little to no great power). Umberlee watches the sea’s and creatures massive waves and storms to those vessels that travel the sea’s but do not give her any honor as they travel across her domains. Talos the God of destruction may decide “just because” that an earthquake should break out along the DragonCoast area and there are 20 deaths because of it and many lives ruined. Tymora may watch one mortal that venerates her one day, giving them the best of luck and then the next day she focuses her sights on another mortal who venerates her. And so on so forth. The mortals in the Realms know the Gods exist because of the last two Godswar’s where the Deities of the Realms took Avatar forms and took the world of Toril as their battle grounds. These Godswar’s nearly destroyed the Realms, another one could very well in fact destroy the Realms forever.

 The Gods of the Realms needs worshippers, and they gain power from the sheer number of worshippers that they have. Thus to their most devout worshippers (their specialty clerics) they give extra powers to that their normal worshippers or other clerics do not receive. Another thing that the Gods give to their mortal worshippers  is the ability to have certain magics work on them if used by a priest of the same deity.
These spells are:
  Resurrection
  Raise Dead
  Heal
  Restoration
  True Resurrection
  Mass Heal
 

 These magics can also be worked by a priest of a “Ally Deity” to the the Deity of the person that the magic is needed to be worked upon…
  Thus if you have a Mage that needs to be Resurrected  that worships Mystra but no priest of Mystra is nearby that could possibly work that level of magic, however you know that Mystra is superior to Azuth the Lord of Mages and that they are Allies you could take the mage to the temple of Azuth to have the magic worked upon him In this case the magic would work on the mage. However if you took the mage to a temple of Tymora the magic would fail, and they would politely tell you in their own way that you should take him to the place of his Goddess to be healed.
 
*In all situations though the being brought back from the Dead will LOSE 1 experience level (being placed midway between a level lower than current level) due to the strain on the soul of the being being pulled out of either the beings Deities Domain or out of the Fugee Plane (the plane where souls recently deceased first go, and where the Gods servants shall pick up the faithful souls, those faithless souls will go to Deaths Domain!) This pulling the soul back into its physical body is very hard, and thus a experience loss occurs. If the being was 1st level, then the being loses a point of constitution that cannot be replaced by any mortal magic.