The Silver Tree

You will find the priests of The Silver Tree in every corner of the world and while they still represent the biggest religion, they are facing a slow and painful decline. The core belief of this religion is that money corrupts and amassing wealth goes directly against human nature and it is therefore sinful. The only ones who should be ever allowed to hoard gold, silver, gems and other precious items are gods and therefore all of the wealth of the world should be gathered at their temples and used to worship them. The entire church is named after the first and most famous temple that was built with donated silver that was used to adorn a hollow husk of an extremely old oak tree that was striken by lightning some decades past which was also seen as a sign of gods of where should people congregate and bring presents to them to appease them.
This was a very useful and profitable way to run the society ever since the ancient times, especially since kings and other rulers were seen as gods representatives sent among mortals to see that the human society prospers and flourishes. This was true for only selected rulers among many and money did what money does truly best - corrupting. Even though the religion itself grows unpopular with every passing day, especially among commoners, it amassed considerable power thorough the millenia.
But as the times went by, one crazy ruler or a high priest after another, people became disillusioned and as the goverments became more and more secular, with rulers wanting to surround themselves with ministers rather than money hungry priests, the church has already lost a considerable chunk of their influence.
The church is represented by the High Priest who is seen as more of a face of the religion and not as someone who wields actual power. This representative is elected by a conclave every ten years or upon the previous High Priest's death. The conclave is a group of 12 senior members of the church and they are seen as the most influential and important religious representatives in the world. Most of them decide to live very secluded and private lives, not wanting to draw undue attention to themselves. There has been however a very recent controvers that allowed the public to peak behind the curtain of the conclave machinations as one of its members recently resigned from his post and was very vocal about certain unsavoury deeds of three other members. He didn't managed to say much before his assassination, but there are still anonymous letters that he has written in advance being published every week or so in different newspapers all over the world, exposing secrets that the church would want to hide forever. It is currently the biggest obstacle this religious group is currently facing, further undermining their position in the public eye.
Because there are many other organisations who would like to have more money, this church has also attracted many enemies with some organisations holding a long time grudge against them. The biggest part of the population that has grown drastically discontent with the pristes are commoners and small merchants. The other influential group that do not like the silver tree are the wizards who need many valuable components, metals and stones for their magical experiments and they are very hard to come by when majority of the mines belong to the church along with hundreds of treasuries all over the world. 
As far as allies, the nobility always viewed the priests as their brethren, many sending unmarried sons and daughters into their service to grow the influence and power of their family and enjoy some of the divine favours that are not available to many. The church has also been a great patron to the arts, using it as a way oof propaganda and getting the public opinion back on their side and commissioning huge monuments and other public buildings that are ornately decorated yb the most skilled artisans.
One of the biggest branches (get it) of the church is solely devoted to charity, with many different subgroups taking care of specific members of the society such as single mothers, sick children, veterans of the war, people without home and also injured animals. It is said that a hospital of the silver tree is one of the prettiest places to die and it is the closes place to heaven.
If the church needs any other allies or favours, money will usually do the trick. And it works both ways. Don't call it a corruption though, at least not to their face. Anyone can get sick any time and you still want to end up in heaven, don't you?
Their main seat of power is next to the city hall that many call the Silver Taverna instead of a temple. It is the biggest and most lavish establishment, whose first floor is fully dedicated as a kitchen for the poor that hands out free food to the public. It usually is not much, but who would complain against a portion of a warm stew and a piece of stale bread, if you have nothing but the street itself to keep you company.
Any potential new members must prove their utmost devotion to the church, the gods and to weeding out evil from the world. Even those belonging to a noble house must go through some rigorous tests, although full pockets can definitely help you achieve better results than you would have otherwise. If you complete the trials successfuly, you will get a tattoo of a tree in white or silverish colour done on your forehead to signify your life long devotion to the cause. The tattooing itself is a part of public celebration and new priests are definitely judged not just by their colleagues but also by the public on the amoung of time they flinch away from the needle. That can set off your entire reputation in the church for years to come.