Warrior Priest of Sigmar

"We must be ever-vigilant, for if we become unwary and weak the enemies of mankind will devour us utterly. Place your faith in Sigmar to protect you, place your trust in your Emperor to lead you, and put your strength in your sword to deliver you from those who would destroy your Empire."

- Warrior Priest of Sigmar

The Warrior Priests of the Church of Sigmar are a warrior-sect of Sigmarite Priest whose duty is to not only lead and inspire Imperial troops on the field of battle, but also to minister to their spiritual needs against the Empire's foes. Sigmar is a Warrior God, and to pursue his creed is to live a life dedicated to battle for the good of all Mankind. The Cult of Sigmar demands that its followers fight all forms of evil in the world with the strength of their arms as well as their faith and many of its priests accompany the Empire's armies when they march off to war, following and honouring that creed. It is thanks to these tireless warriors that a rousing speech by a Warrior Priest of Sigmar has restored the troops' faith, brought hope to a seemingly lost cause, or prevented a mutiny when the words of even the most respected commanders had fallen on frightened and angry ears.

Throughout the Empire it is considered only right and proper to honour all the gods and even those priests who serve only one deity will still show respect to other gods in appropriate situations or when their portfolio is predominant. But where the older gods are seen to care little for the plight of Men, Sigmar is the patron of the Empire and its people, the reason why the people of the Empire often refer to themselves as Sigmar's People and venerate the sigil of the Twin-Tailed Comet. This remains true in every province of the Empire, even in those places where Ulric, Taal, and the other gods are more actively worshipped than the Heldenhammer. The High Priest of the Cult of Sigmar is known as the Grand Theogonist, and he is served by two Arch Lectors. Beneath these ecclesiastical officials, all three of whom serve as full Electors of the Empire, are the Warrior Priests. Almost every town and village in the Empire has at least one shrine dedicated to Sigmar and so Warrior Priests of the deity are a common sight wherever the writ of the Emperor's law extends.

In battle, the divine power of Sigmar stirs within their hearts and his divine might is their command, allowing them to perform extraordinary miracles in the name of their god, so long as their faith in him remains strong. A Priest of Sigmar can unleash the Heldenhammer's wrath to smite creatures of darkness like daemons and Undead or even less malevolent beings like Forest Spirits, call upon divine protection for fellow Imperial warriors engaged in battle to enhance their defences or even return a badly wounded comrade from near death, miraculously healing all his wounds. To see such blatant signs of Sigmar's favour fires the hearts of all Men and leads them to redouble their efforts to defeat the foe. Warrior Priests of Sigmar normally wear mail or full plate armour underneath their holy vestments, wield the mighty warhammers that are the favoured weapon of Sigmar, and ride into battle atop powerful Imperial warhorses. Among the most commonly employed divine powers of a Warrior Priest are prayers.

Source
Warhammer Armies: The Empire 8th Edition -- pg 36