The church is the bastion against darkness and the Guardians are those who protect humanity and the Empire from destruction. They are willing to do whatever it takes to safeguard the Empire under heaven.
“Thinking evil is not doing evil, the difference lies in the act”
Stemming from traditions of warrior monks, their role and doctrine revolves around honing body, mind and community for the defence of the Church, in many forms. Tending to Church and Empire like one would to a garden, they are security and local police on Andophael, often have jobs as PRISM relations making sure that the name and reputation of the church is defended, and participate heavily in the High Church's counterintelligence efforts.
The Guardians do not glorify conflict or strife, but do see it as an inexorable part of life that needs attention and tending to.