What are the Pathwalkers

[Enkidoh]

Yeah, it was just a term given to members of the Path of the Twelve ('path', 'walk', get it?), but it was also a term used by Minfilia in version 1.0 to describe the both metaphorical and physical journey undertaken by members of the Path to uncover the secrets of the Echo.

Minfilia actually remarked when a player first joined the Path that there were many Walkers (i.e. Echo users) who had set out to investigate the Echo, and that not only did many never return, every one who did had been changed by the experience, refusing steadfastly to reveal exactly what it was they had discovered, as mentioned here:

Minfilia: "Very good. I pray together that we can learn more of this gift... for though we have scoured the realm for nigh on ten years, I fear there is still little we understand."
Minfilia: "Scores of men and women have passed through our doors looking to find answers, and scores have embarked on quests to do just that... but their efforts have gained us little... and many have not returned."
Minfilia: "Of those few who have... not one is willing to speak of what they saw at the end of the Path. It is as if they all bore witness to a truth too terrible... or too shameful to be told."
Minfilia: "There are those here who would have me use the Echo to delve into the past of the returned. Yet it would be wrong of me to use my gift to tear that truth from them against their will. Were I to condone such an act of violation, we would be no different from the monsters people think us already."

In some respects the Path of the Twelve was run a little differently to how it's successor post-Calamity is operated - here the Path was very much a research Guild devoted simply to the study of the Echo and the subtle use of it to better the lives of the people of Eorzea. Minfilia adopted a strictly pacifistic approach when it came to interacting with the citystates - in fact, none of the citystates even knew it existed, other than the Ala Mhigan Resistance.

Additionally, a great deal of their members (the titiual 'Walkers') were ordinary people and not just adventurers, merchants, craftsmen, even young children), so Minfilia took great care to only assigning those who she thought could handle a certain situation to the most potentially dangerous tasks (which naturally ended up being the missions the player was sent). As a final safeguard, Minfilia would assign Walkers partners who would work together on missions given by the organization, whom were called 'Path Companions'.

In any event, this all became moot after the Calamity when a great deal of the Path's members were wiped out in the Battle of Carteneau, and thus Minfilia and the surviving members were sort out by the Circle of Knowing, who decided to pool their resources and amalgamate to form the Scions of the Seventh Dawn.

So yeah, the term 'Walker of the Path' was basically version 1.0's equivalent of 'Scion of the Seventh Dawn'.