I'm posting this stuff largely for my own benefit, there are no big secrets here but if I post material here I can get it at home and not worry so much about emailing myself anything that occurs to me during work. It's also pretty dry stuff now I look at it.. anyway.
Evangelists are the special forces of the New Crusade (the terms "New Crusade" and "Church" are largely interchangable at this point), they are granted the power of God to implement his will on the heretics. They are granted a certain number of powers based on their rank within the Church, their innate ability to channel these powers and how much they have earned the right to use these powers.
New Evangelists come into their powers suddenly and in all cases the granting of these powers are marked by a period of amnesia covering a period of two to three weeks, it is theorised that the human mind is ill equipped to deal with the sudden granting of a spark of the divine. In almost all cases the church manages to care for these poor souls during the period of amnesia, preventing them from injuring themselves as they wander around in a daze, a state that, were they on the streets, would almost certainly end in their being mugged, raped, attacked or killed by the human predators that wander the earth.
Evangelists recognise what has happened to them and without exception devote themselves to the New Crusade (since the Lord would surely not grant his powers to someone who would use them for ill) and are a valuable resource who are cared for by the New Crusade though the Evangelists ask for little and the Crusade asks for much in return. Their lot in life is to infiltrate the heretics and destroy them, to seek out sin behind locked doors where the Clergy may not go and to always work in secret.
The Evangelist's powers are many and varied, they are refered to as "Prayers" or "Catechisms", they are very specific in their use and purpose. New or unique Prayers are occasionally granted but this is the exception rather than the rule but as things change, so too do the frequency and availability of these powers as some older ones disappear, never to manifest again.