But at the same time a strange mystical pantheistic tendency became noticeable in many sermons and lessons of the Church herself. All this multitude of heretic Beguines, suddenly made orthodox within three days, all this vast accession of vague Almarician piety was not without an influence on the conquering faith. Among the Dominicans of Strasburg the mystical bent grew more decided year by year. These much-admired doctors and magisters were lights of the Church, men of influence and learning; but the mysticism which was orthodox in them was really identical with the neoplatonist theories of the Beghards. And, indeed, these men,—Eckhart, Tauler, Rulmann Merswin—went further in the way of pantheism than the heretic brotherhood had gone before.
It is impossible to exterminate an idea. It must live its course, grow, flourish, and die. Be it wise or foolish, orthodox or heterodox, let it but have some new aspect of truth in it; let it but be fresh, profound, and striking; let it be truly and verily an idea: it will live its life before it dies its natural death.
Thus the idea of the Beguines, arbitrarily suppressed, yet flourished only the more. Like a brier budded on a rose tree, it brought out its wild and fragile blossoms among the ordered beauties of the ecclesiastical garden. In the great Dominican mystics of Strasburg the central thought of heretic Beguinism (“_Deus est omnia_”) flourished more completely than before.
God is all: the world is nothing. This is what the mystics of Strasburg and the mystics of the Netherlands now began to preach to the world.
From the year 1312 until 1320 Master Eckhart, the great Dominican preacher, was living in Strasburg. His deep and original mind, which so vastly was to influence the speculation of his time, was now itself brought under the influence of Beguinism. From 1312 to 1317 he preached and visited in the Dominican beguinages of Strasburg. Always a mystic and a neoplatonist, before that date he was not suspected of heresy. The theories of the Dominican Beguines agreed perfectly with the convictions of this singular being, who preached in accents of strenuous sincerity the doctrine of the unreality of matter.
Among the Beguines of his diocese was one whom Eckhart adopted to be his spiritual daughter. But the relation of the Beguine Sister Katrei to the great Vicar-general of the Dominican order was scarcely that attitude of submission which we expect from a penitent to her confessor. She leads him on to new audacities of faith, suggests new penances, refuses all restraint. She shows him how an earnest nature can reduce to practice his special tenet that the world is nothing, that God alone exists.