Then comes the Spirit to our hut, When fast the senses' doors are shut; For so Divine and pure a guest The emptiest rooms are furnished best.[496] Or, in the words of one of the saintliest of the mediaeval mystics, 'In the chamber of the heart God works. But what He works in the souls of those with whom He holds direct converse none can say, nor can any man give account of it to another; but he only who has felt it knows what it is; and even he can tell thee nothing of it, save only that God in very truth hath possessed the ground of his heart.'[497] It may here be observed that what has been said of Quakerism, so far as it was at one time representative of that mystic element which the eighteenth century called enthusiasm, will be a sufficient reason for passing all the more briefly over other branches of the same subject. The idea of self-surrender to the immediate action of spiritual influence is a bond of union far more potent than any external or ecclesiastical differences. Whatever be the period, or Church, or state of society in which it is found, mysticism is always very nearly the same both in its strength and in its weakness. It exhibits, indeed, the most varied phases, according to the direction and degree in which it falls into those excesses to which it is peculiarly liable, but such extravagances are very independent of the particular community in which they happen to appear. Different as are the associations connected with such names as Plato and Pythagoras, Plotinus and Dionysius, St. Bernard and T. a Kempis, Eckhart and Tauler, More and Norris, Fenelon and Guyon, Arndt and Spener, Law and Byrom, Quakers and Moravians, Schleiermacher and Schelling, yet passages might be collected from each, often striking and sometimes sublime, which show very close and essential points of affinity. And just in proportion as each form of mysticism has relaxed its hold upon steadying grounds of reason, the diversified dangers to which it is subject uniformly recur. Every successive type of mystic enthusiasm, if once it has passed its legitimate bounds, has produced exactly analogous instances of pantheism, antinomianism, or fanaticism.