Psalm 91:11, he will command his angels concerning you to guard you in all your ways, and Matthew 18:10, their angels in heaven always see the face of my Father, are the twin pillars. Jerome read Matthew as proof each soul has an assigned angel; Aquinas agreed, every living human possesses one, drawn from the lowest choir. Acts 12 shows the early community assuming Peter's angel could stand at a door knocking. The Catholic feast of the Guardian Angels dates to 1670.
Personal divine guardians predate Judaism's angels: Zoroastrianism's fravashi, the pre-existing soul-double that guides and protects, Plato's personal daimon, Rome's genius. Each person a patron spirit is close to a human universal, and the angel version is the local dialect. The Persians, again, are standing in the family photo.
The claim: assigning every human a permanent invisible witness is the oldest panopticon, conscience outsourced to a reporting officer, and the doctrine's practical function, behavior under observation, survives secularization as the camera in every pocket. Verdict: the tradition itself leans the other way, the angel guards more than it reports, but the structural observation stands: a cosmos where no one is ever unobserved trains a certain kind of soul. Whether that soul is comforted or managed depends on who is watching the watchers.
If everyone has one, when did heaven get so bureaucratic, or did we?