Question not your lot in this life. Be content to serve the Emperor – however, humble your station.

– Anonymous Amalathian Preacher

The Amalthians are perhaps the most typical of the Imperialist sects, embodying the definition of the movement. The start of the 41st millennium was a time of spiritual and physical rebuilding for the Imperium. A great conclave was held on Gathalamor, at Mount Amalath, where military, religious and political leaders and dignitaries gathered in their thousands to swear once more their oaths of loyalty to the Emperor and Mankind. It was this gathering that spurred Macharius to his conquest of nearly a thousand worlds, and during this time there was a swell of optimism within the Inquisition that everything was once more proceeding as the Emperor had planned, in contrast to the widespread pessimism that pervaded before and after the Reign of Blood and Plague of Unbelief.
The first and largest of the Imperialist sects, the Amalathian movement attracted large numbers of followers, believing that it was their sacred duty to let nothing threaten the strength which the Imperium was regaining. They strive to maintain the status quo, seeking out any person or agency that might destabilize the power of the Imperium from without and within. They are less concerned with the more traditional crimes of mutation, witchery, and religious heresy except where these conflict with the institutions of the Empire of Man. They try to keep the rivalry and politicking between the various Imperial Organizations to a minimum, holding to the Inquisition’s original creed of strength through unity. Change is considered the most serious threat of all, for change can herald disaster.

While other sects of the Ecclesiarchy may endeavor to bring about some great upheaval or revelation that will see Mankind break from its current turmoil into a new golden age, the Amalathians prefer to progress slowly, if progress is necessary at all. The Amalathians accuse Inquisitors of other philosophies of utter arrogance in claiming that they know the Divine Will of the Emperor. Amalathians trust the Emperor to work His way and His plan as he has always done, and it is for the Inquisition to maintain the Imperium so that he may do so as He sees fit – mortals do not try to guess the Emperor’s mind. At its heart, the Imperium is the Emperor embodied and to protect the Imperium is to protect the Emperor.
Amalathians work hard to root out factions and cults which would destabilize and threaten the power of the Imperial organizations,  Imperial commanders, military leaders, and so forth. They openly and actively support these parties and grant them tremendous leeway to protect their own positions, where it does not threaten the status or power of other organizations and individuals. They are very wary of any change at all and closely adhere to the dominant beliefs of their time and society.
The Amalathian sect strives to shield the Imperium from the worst ravages of aliens, cults, religious schisms, and mutation. They work well with agents from other Imperial agencies, as the interests of the Adeptus Mechanicus, Imperial Commanders, Ministorum, and other organizations are also the interests of the Inquisition. They work particularly well with the Adeptus Arbites and local security forces whose duty it is to enforce Imperial and local law, thus defending the power of the Imperium itself.