"Now concerning the Eucharist, give thanks this way. First, concerning the cup: We thank thee, our Father, for the holy vine of David Thy servant, which Thou madest known to us through Jesus Thy Servant; to Thee be the glory for ever.The Didache makes no mention of the Last Supper, or of the “body” or “blood” of Christ. It appears that for the earliest Christians the "breaking of bread" was a communal meal and was not viewed as a "memorial" of Christ's death.
And concerning the broken bread: We thank Thee, our Father, for the life and knowledge which Thou madest known to us through Jesus Thy Servant; to Thee be the glory for ever. Even as this broken bread was scattered over the hills, and was gathered together and became one, so let Thy Church be gathered together from the ends of the earth into Thy kingdom; for Thine is the glory and the power through Jesus Christ for ever."
It wasn't until Augustine of Hippo (355-430 AD) who was heavily influenced by Neo-Platonism and Greek and Roman rhetoric that the concept of “original sin” was developed. Augustine argued that the effects of “the Fall” were transmitted to Adam’s descendants who inherited his guilt. (He was also the first to demand that the “sacrament” of Eucharist had to be performed by ordained clergy in order to be valid.
For the first time the atonement began to be tied to the celebration of the Lord’s supper, the validity of the sacraments [and sacraments performed by dissidents were regarded as invalid], and the authority of religious leaders). He laid the groundwork for theologians such as the fourth century Gregory of Nyssa who argued that Christ’s death was a ransom paid to Satan, and the eleventh century Anselm of Canterbury who developed a “satisfaction” theory, arguing that the debt was in fact paid to God. Thomas Aquinas and John Calvin further refined these theories into the view that Jesus’ death was necessary to meet the demands of divine justice.