Wise One

Wise One was a title given to the members of Gathering who had undergone training there and, after having been an Initiate for a while, proved their skills and discernment and served well the Goddess. Occassionally the title would be accorded to Mages, Priestesses, or scholars, who didn't study at Gathering but proved their merit ohterwise and were widely recognised as exceptional individuals.
Because there was no predicting when someone would be recognised as worthy of the title, the ceremonies usually took place by the way, as the selected individual arrived at Gathering for some other reason, like celebrations or councils. There was no special mark that would come with the title, it was just a matter of recognition.
The decision when someone was ready to receive it was usually achieved unanimously among the Gathering's permanent Council, and if there were any doubts, the award would wait. However, the authority of Rectoress in the times of Arielle was so great, that her voice was de facto decisive.
Becoming a Wise One didn't have much practical implications, but it did have a lot of impact on how people perceived a person and sometimes could result eventually in some sort of advanacement - if desired. For instance, only Wise Ones would become king's advisors usually, but not all Wise Ones had such desires at all. Many of them continued a life of quiet study, or service to the communities they lived in, whether through healing or through counsel. 
The title once awarded remained for life. Even if a Wise One committed any crime or went against the values of Gathering and against the Goddess - there was no taking it back. There were times when this was hotly debated, especially after the Alaric's betrayal, but in the end the members of the council agreed that they didn't have the authority to condemn people they had once deemed good enough to be named Wise Ones.