Templar Armor (Origins)

Traditional Templar Armor, worn by all guardians of the Chantry.

Acquisition

The armor can be obtained from the Bewitched Templar. When you approach him, you converse with a Desire Demon. You can either leave them alone or attack. During the battle, the Demon summons skeletons. Once you kill the Templar, this armor is available.
You can obtain the Templar Helm from a Possessed Templar on a lower floor.
The Templar Gauntlets and Templar Boots are not available in Dragon Age: Origins.
In Dragon Age: Origins - Awakening, a pair of Templar Boots can be found as a random drop during the quest Freedom for Anders. These boots can be worn but due to a bug they cannot be seen and will make the character's lower legs invisible from the knees downward while wearing them.
Also, a Pair of Templar Gauntlets can be dropped in Dragon Age: Origins - Awakening. These can be seen and used but have no attributes.

There is no item set bonus for wearing this armor.
Bioware, for some odd reason, decided not to put normal Templar Gauntlets and Templar Boots.
In Dragon Age II, the Templar Wesley will be wearing a more streamline version and many Templar used a different armor of the original armor. Unknown if these armors will be aquired.
A 2011 playthrough of Dragon Age: Origins did in fact allow the full Templar Armor set to be collected from the Mage's tower - Shield, Helm, Gloves, Armor and Boots, complete with item set bonus. The majority of the items were looted from possessed Templars on the "Grand Hall" level. Whether this was enabled by an add-on, an official patch or one of the expansions is impossible to determine, but it is definitely possible to get the full set without having to play Dragon Age: Origins - Awakenings. NEED CONFIRMATION BY OTHER PEOPLE, MANY TEST WITH PATCH 1.4 AND NEVER HAD THE REST OF THE ARMOR.