The Adornment of the Spiritual Marriage, by Jan van Ruysbroeck, , at sacred-texts.com
By this fierce ardour and this impatience some men are at times caught into the spirit, above the senses; and there words are spoken to them and images and similitudes shown to them, teaching them some truth of which they or other men have need, or else things that are to come. These are called revelations or visions. If they are bodily images, they are received in the imagination. This may be the work of an angel in man, through the power of God. If it be an intellectual truth, or a ghostly image, through which God reveals Himself in His unfathomableness, this is received in the understanding; and the man can clothe it in words in so far as it can be expressed in words. Sometimes a man may also be drawn above himself and above the spirit (but not altogether outside himself) into an Incomprehensible Good, which he shall never be able either to utter or to explain in the way in which he heard and saw; for in this simple act and this simple vision, to hear and to see are one. And none can work this in man, without intermediary and without the co-operation of any creature, save God alone. It is called Raptus; which means, rapt away, or uplifted, or carried away. At times God grants to such men a sudden spiritual glimpse, like the lightning in the sky. It comes like a sudden glimpse of strange brightness, shining forth from the Simple Nudity. And thereby for an instant the spirit is raised above itself; but the light passes at once and the man returns to himself again. This is the work of God Himself; it is something very sublime; for those to whom it happens often become illuminated men.
Other things sometimes happen to those who live in the fierce ardour of love; for often another light shines into them, and this is the work of God through means. In this light the heart and the desirous powers uplift themselves towards that light; and, in the meeting with that light, the joy and the satisfaction are so great that the heart cannot contain them, but breaks out in a loud voice with cries of joy. And this is called the Jubilus, or jubilation; that is, a joy which cannot be uttered in words. 46 And one cannot contain oneself; but if one would go out with an opened and uplifted heart to meet this light the voice must follow, so long as this exercise and this light endure. Some inward men are at times taught in a dream by their guardian angels or by other angels, concerning many things of which they have need. Some men too are found who have many sudden intuitions, or inspirations, or imaginations, and also have miraculous dreams, and yet remain in their outward senses. But these know nothing of the tumult of love; for they dwell in outward multiplicity, and love has not wounded them. These things may be natural, or they may come from the devil, or from good angels, and therefore we may have faith in them so far as they accord with Holy Writ, and with the truth, but no more. If we trust them beyond this, we may easily be deceived. 47