Claims not only to experience God’s presence but also some kind of union with God occur throughout the texts of early Christianity; they are arguably found in Augustine and also in Clement (d. c. 215), Origen (c. 185–254), Gregory of Nyssa (c. 335–94), in the texts attributed to Dionysius the Areopagite (c. 500), and in a host of martyrological, hagiographical, and monastic texts. In the medieval west, the influence of Augustine and Dionysius looms largest, and both suggest – without clearly asserting – that union involves a dissolution of the self before and in God. Yet the mainstream of the Augustinian tradition, represented by the work of Bernard of Clairvaux (1090–1153) and his fellow Cistercians, as well as that of the twelfth-century Victorines and much thirteenth- and fourteenth-century Franciscan mystical writing, insists on a union of wills in which the soul maintains its identity as other than God even as it feels as if that distinction is lost.

The notion of a union of wills remains central to the theological articulation of mystical experience throughout the Middle Ages. Yet there is a counter-trend, one first visible in northern Europe in the late thirteenth and early fourteenth centuries (although there is evidence for similar views espoused contemporaneously south of the Alps). The beguines Hadewijch (c. 1250) and Marguerite Porete (d. 1310) and the Dominican Meister Eckhart (c. 1260–1328) suggest that complete union with God occurs when the soul not only overcomes its sinfulness, but also its very creatureliness or createdness. Hadewijch hints at this view in a vision in which an angel shows her an ideal, ‘full grown’ Hadewijch who is enclosed within the deity and who has never fallen into sin. Marguerite Porete goes further, arguing that the truly free and annihilated soul – one who has not only overcome her own sin and will, but who has also destroyed reason, will and desire – exists there ‘where she was before she was’.

Meister Eckhart provides a Neoplatonic framework for such claims. In his commentary on the Prologue to the Gospel of John, Eckhart draws out his understanding of the self-birth of the Godhead, the external emanation of all things from the divine source, and the return of all things to God. Playing on the double meaning of the Latin term principium, Eckhart argues that the opening of the Gospel (‘In principio’) refers both to the temporal beginning of all things and to their source or principle. For Eckhart, following The Book of Causes and other Neoplatonic sources, that which ‘is produced or proceeds from any thing is precontained in it’ and ‘it is preexistent in it as a seed in its principle’. Moreover, that which proceeds not only pre-exists in its source, but also remains in its source ‘just as it was in the beginning before it came to be’. All created things, then, have their principle in an other and that principle remains in the other. All of creation has both a virtual and a formal aspect – it therefore has both coeternal and temporal relations to the divine. The grounds for the return of all things to their divine source lies here, for all things have their principle in the divine and, insofar as they remain uncreated with that divine ground, eternally participate in the self-birth of the Godhead and of all creation.