Do resources score twice (once for the corresponding temple and once again for every 1/3)?
If I have the temple for wheat and 6 wheat in my inventory, is that 12 points or 14?
The resources score twice. The descriptions for the temples include a colon (or equals sign, depending on the version), so you don't surrender the resources to get the points. (The copy of the rules I have handy also explicitly says not to discard resources when scoring a temple that uses resources for its scoring.)