The Test of the Eye is a ritual administered by the White Mantle to discover civilians possessing True Sight. This is done through the Eye of Janthir, and according to the White Mantle administering the Test is a high honor. The Chosen discovered by the Eye are supposedly taken for training and indoctrination into the White Mantle, often to the ire of other peasants who are short of manpower for their farms.
Warning: The following text contains spoilers relating to the plot of the Prophecies PvE campaign.
After being accepted into the White Mantle, players administer the Test of the Eye at Divinity Coast. The player must be cleansed in order to receive the Eye of Janthir, which follows them along their journey to the coastal village of Loamhurst. The Test is administered by simply bringing the eye near a civilian. Chosen villagers will often be indicated on the compass, and when approached by the Eye they will be surrounded by a bright aura. Villagers who do not possess true sight will be knocked down by the Eye. Interestingly, or perhaps a hint at future plot developments, none of the White Mantle are indicated to be Chosen by the Eye of Janthir.
At the completion of the mission, the Chosen are led into Maguuma Jungle by the White Mantle but are abducted by the Shining Blade rebels, who later reveal to the player that the Chosen selected by the Eye are sacrificed in the jungle on a Bloodstone.