WHY DO SOME PERSONS SEE VISIONS?
By visions we mean, not what we see in dreams, but what is perceived in reality by the senses. A vision is the appearing of the Deity, angels or saints or even of evil spirits.
Since spirits do not have bodies, they cannot really be the object of the senses. Spirits therefore have to assume a material form so as to be perceived by the senses. A vision, then, is the corporeal appearance of a spirit.
Scripture is full of instances of supernatural appearances, from the early chapters of Genesis to the Apocalypse. In the history of the Church too there have been numerous visions from the earliest days till recent times. We are familiar with the apparitions of Our Lord to St Margaret Mary at Paray-le-Monial (1673) and of Our Lady to Bernadette at Lourdes (1858) and to the three children of Fatima (1917).
Visions are intended for the spiritual good, not primarily of the visionaries themselves but of others, although the visionaries too could be greatly benefited, spiritually by the extraordinary supernatural experience. For instance, we see in the revelations of the Sacred Heart to St Margaret Mary, and the messages Our Lady made known through Bernadette at Lourdes and the children of Fatima, God's concern for mankind. Visions are therefore distinct from the divine enilghtenment bestowed mainly for personal sanctification on such mystics as St Iohn of the Cross, St Teresa of Avila and St Catherine of Siena.
Although we generally mean by vision what is corporeal, that is, what can be known by the senses, mystical writers speak also of ‘imaginative’ and ‘intellectual’ visions. Imaginative visions result from the supernatural impression of an image on the memory, apart from what is perceived by the external senses. By intellectual vision is meant the intuitive understanding of some supernatural truth without any impression on the senses.
Authentic visions have of course to be distinguished from illusions or hallucinations resulting from pathological conditions or diabolical intervention.
From the point of view of divine revelation visions are of two kinds. First, there are the visions which are the media of revelation of the deposit of faith, for instance the revelation of the Incarnation by the apparition of the angel Gabriel to Mary. Secondly, non-scriptural apparitions of later times for private revelations which do not add to the deposit of faith.
In the case of private revelations, even when the Church, after investigation, approves the visions or apparitions, such as those of Paray-le-Monial, Lourdes and Fatima, they are only proposed by the Church to the faithful as worthy of ‘pious belief’. The Church does not ask us to accept them as matters of faith.
The fact that the Church does not officially approve a vision does not imply that it is not genuine. Credibility depends very much on evidence. The main criterion of the Church in assessing the authenticity of a vision is whether or not its message or revelation concurs with the message of the Gospel.
One cannot be unconcerned about visions since they are a means by which God may convey a message. On the other hand, one has also to guard against vain credulity. It would be safe for one to follow the guidance of the Church in this matter.