Allegory is derived from the Greek word allegorein meaning 'to say one thing openly but to imply something else'

Allegorical interpretation first emerged from Stoicism and by the first century AD was the dominant way to interpret all philosophy and was always didactic on purpose. As Christianity spread into the Hellenized world it became natural that scripture would also be interpreted this way given the purpose of scripture is to reveal God to humanity. Indeed, Jesus use of parables might be taken as endorsement of such interpretation. Though CH Dodd strongly disagreed.

In the context of Platonic separation of physical world from the 'higher' spiritual one allegory speaks of the higher plane in terms familiar from the physical world. It is easy to see how this could quickly lead to gnosticism.

Origen of Alexandria sought to translate the already ancient events of the old testament into a contemporary experience and understanding of God for his flock.

Bostock explains