Monastic Profession as 'Second Baptism' in Seventh Century English Monastic Orders

From Ritual and the Rood; Liturgical Images and the Old English Poems p. 295:

The circle of Theodore of Canterbury gave fresh impetus to such ideas in England in the second half of the seventh century. The Capitula Dacheriana associated with Theodore presents onastic profession more explicitly than any Western rule as a 'second baptism.' To become a monk is a second conversion a paenitentia secunda which obtains forgiveness from all previous sins:

In the ordination of a monk the abbot should celebrate Mass and recite three prayers over his head. And let him veil his head for seven days in his hood; and on the seventh day let the abbot take that veil from the head of the monk. As in baptism the priest takes away the veil of the infants on the seventh day, so should the abbot do to the monks because it is a second baptism according to the judgement of the Fathers and all sins are forgiven as in baptism.

This ritual of profession was clearly modeled like the Ruthwell Cross, on the rites of Christian initiation culminating in the Eucharist.