The 7 sacred Virtues (Faith, Hope, Charity, Prudence, Justice, Fortitude, Temperance) clockwise
This was an idea Ikran had since Season 2 of Sleepy Hollow. And, oh boy, it had been on a constant shift. Basically, the seven virtues were the polar opposites of the Seven Deadly Sins, consisting of the 3 Theological Virtues (Faith, Hope, Charity), and the 4 Cardinal Virtues (Prudence, Justice, Fortitude, Temperance). Seven individuals were chosen to save the world during the apocalypse and aid the Witnesses; they were their Guardians. It's possible they were passed down by other allies/ancestors. Here's the layout from the top clockwise:
Season 2[]
Faith - Katrina
Hope - Jenny
Charity - Hawley (regretfully...)
Prudence - Chief Turgado
Justice - Abbie
Fortitude - Gavin
Temperance - Ichabod
Season 3 was tough, as the Onondagas have relocated back to their homeland, and the characters and villains were awful; this was the dark age of the series.
Season 4 and the Missing Episodes[]
Faith - Jenny
Hope - Jake (she was on the fence with this)
Charity - Alex (she was on the fence with this)
Prudence - Ichabod
Justice - Diana
Fortitude - Gavin
Temperance - Lara (Molly's future vessel)
More is explained in Chapter III - The Seven Sacred Virtues.
There was a brief period where the team's fallen friends have discovered that it was time to bestow them with seven sacred virtues. Each individual would have a certain virtue depending on their own attributes. Gavin was the first to notice the back of his hand suddenly ignite and reveal a seven-shaped crystal that showed a cross in the center and one of the corners light up. Eventually, the others noticed the same thing, but at different spots.
Before that Gavin was in a temporary trance as Turgado said in his tongue, as Ichabod translated, "When the seven symbols unite, evil beware of its plight." It was then they realized they possessed the seven virtues, the polar opposites of the seven deadly sins. Ichabod had Prudence, the governing virtue, and Lara came to the conclusion that Witnesses before him, such as Moses and Elijah, had it. Then Washington when he chose Ichabod as the leader of Agency 355, then Turgado since he was a gifted shaman, and finally to him.
Gavin has Fortitude from his ancestor, Leon. The Mills, Grace Dixon then Lori Mills, passed down Faith to Jenny and Justice, which was Abbie's/August Corbin's virtue to Diana. Alex got Hope and Jake got Charity from the former workers at the Vault (Paul Jennings for Jake), and Lara got Temperance from how she was raised. They also found out that several guardians were chosen to protect the Witnesses from persecution and danger, they turned out to be them excepting Lara and Crane. From those pieces fitting into place, and the copy he found of the lost tablet containing the virtues, Ichabod now noticed about the nature of his destiny as a Witness and why he was born as a leader. It was up to him to save the world from evil, just as Washington predicted.