The spark metaphor is chosen deliberately. A spark is both a part of a fire and distinct from it; it goes out into the world but carries the original flame. So the soul carries within it a point of divine fire that the world cannot touch. Sin can coat the outer soul; it cannot reach the spark. Even in the most sinful person, Eckhart preaches, this innermost point remains uncorrupted — not because of moral achievement but because it belongs to God by nature.
Eckhart pushes further than the tradition. It is not that the spark resembles God or images God; it is, he insists, identical with the divine ground. The outer soul is created; the spark is uncreated. When the soul turns inward and downward to this point, it does not approach God — it finds that it was never separated. The journey inward is also a journey beyond time, because the spark exists in eternity rather than in the temporal sequence of created things.
To reach the spark, the soul must become poor — not in possessions but in self-will, concepts, and even the will to be virtuous. The spark cannot be grasped; it can only be uncovered when everything that covers it is released. This is Eckhart's most provocative teaching: the highest spiritual act is the renunciation of spiritual ambition.
The Fünklein appears prominently in Sermon 2 and Sermon 52 (Beati pauperes spiritu). The inquisitors found Eckhart's language of the soul's identity with God particularly suspect; he defended it as a form of speech (modus loquendi) rather than a heretical claim.
