In Minecraft, weapons can be repaired by anvils. The same goes for some weapons in Divine RPG. However, due to the mechanics of the mod, although items may be repaired, they are not necessarily repaired by the materials they are made out of. Also, none of the weapons (as of Divine RPG 1.2.8) have been assigned with a "repairing material", so some weapons may not be repaired. Combining a weapon with itself (eg. Repairing a Diamond Sword with a Diamond Sword) is not considered to be a repair.
If a "repairing material" cannot be found for a particular weapon, it will be marked with "Unknown". If a weapon has infinite uses, then they do not need to be repaired ,and hence will be marked with "N/A". Below are tables listing all the weapons introduced in Divine RPG (still in development), and what they can be repaired by.
Weapons can also be classified in terms of whether or not they are worth repairing. For example: A Diamond Sword is crafted with 2 Diamonds, but requires a total of 4 Diamonds to repair it completely. Therefore, it is much better to craft a new Diamond Sword, and hence it is not worth repairing. This classification assumes you have not put any enchantments on your weapon.