Righteous Path is a gear perk that refills your weapon's magazine after a takedown. It lets you go straight from a silent kill into gunfire with a full magazine, so a stealth plan that goes loud is easier to recover.
Every takedown tops up the magazine of the weapon you hold. You skip the reload after a stealth kill and are ready if a nearby guard spots you.
Wear the Prophet's Jeans in the legs slot. Gear perks are fixed to the piece of clothing that carries them, so you get this one by wearing that piece, not by unlocking it in a menu.
Quiet Confidence and Takedown Tagger support the same takedown-first approach.