Original sin

Doctrine · On salvation · from 412

Adam’s sin passed to all his descendants, so that infants are baptized for the remission of sin and not only in imitation of him.

Carthage in 418 put it in canons, against the view that Adam harmed only himself. The infant-baptism argument is the one that carried it: the church already baptized infants for remission, and the practice was older than either side.

Held it

412 — Augustine of Hippo (Defends). Argues from the church practice of baptizing infants for remission that the sin they are cleansed of is inherited. New Advent (Fathers and Catholic Encyclopedia) · Augustine, On the Merits and Remission of Sins 1.34
418 — The Council of Carthage (418) (Defines). Rules that infants are baptized for the remission of sin, and anathematizes the denial. The Seven Ecumenical Councils (NPNF series 2 vol. 14) · the African Code, canon 110 (Carthage 418)

In the disputes

The Pelagian controversy How much a man can do unaided.

First stated in this form after The Seven Ecumenical Councils (NPNF series 2 vol. 14) · the African Code, canon 110 (Carthage 418) on the baptism of infants.