The Steps of Faith was added in patch 2.5 of the A Realm Reborn expansion.
The Steps of Faith becomes available at level 50 as part of the “An Allied Perspective” quest, which is given by Tataru – Mor Dhona – The Seventh Heaven (X:21, Y:8) (Main Scenario).
The trial has a minimum ilevel of 90 to enter and rewards you with:
Allagan Tomestone of Poetics: 15