The Path of Light is the religion practiced by many of the Kalashtar, who seek to change reality by bringing about change within, using meditation to focus their mind and martials arts to improve their body. The goal of the Path of Light is to bring il-Yannah, the "Great Light" into the world through compassion and courage, to banish the darkness in the world. They believe that in doing this, in striving to make the world a better place, they can push Dal Quor into the Turning of the Age, into what they believe will be an age of light.
Those on the path believe that the current age of Dal Quor is dominated by il-Lashtavar, the "Great Darkness that Dreams", which poisons the world and drives people to be their darkest selves. They also believe that this can be changed, that if they bring enough light into the world then they can bring that light to Dal Quor, too, and usher in the age of il-Yannah. There are multiple schools of thought around this, with some believing that meditation and reflection alone will be sufficient to change the course of reality, but most believe that direct action is necessary, that the darkness must be fought with the light. They don't believe that violence is the answer, most followers of the Path of Light believe that the only way to truly defeat evil is to redeem it and make it a force for the light, and as such they seek to change lives, enlightening those whose evil is driven by ignorance.
The Path of Light is most commonly practiced by the Kalashtar, though it is widespread throughout Adar. It is almost unknown in Khorvaire, practiced only by the kalashtar and immigrants from Adar.
The symbol of the Path of Light is a crystal, often worn. Martial arts are a devotional practice for Lightbringers, as is guided meditation, who seek to change their minds and bodies in the same way that they seek to change the world. In Khorvaire, there are only a few shrines to the Path of Light (one of which is found in Overlook), but Adar has great fortress-monasteries that are dedicated to the path and defending Adar from the Unity of Riedra.