Little Question Five of Question Three
Why good spirits instruct human beings enigmatically and parabolically, and not clearly
It is doubted why good spirits do not instruct human beings clearly through dreams, but enigmatically and parabolically, since the end in the sending of dreams is the signification of certain things which it is expedient for human beings to know or foreknow.
Simonides the philosopher, wishing to answer this, said that it occurs because God envies mortals their knowledge of future things, and therefore sends human beings dreams about future things not clearly but under obscure coverings of figures.
But because in this he erred most greatly, it must be said that enigmatic and unclear dreams are sent to human beings for many causes.
First, it is so that human beings, terrified by obscure dreams, may recur to the Lord for their interpretation; or at least may ask that he will avert the impending evil; or so that some servant of God may be exalted for the salvation of many and God may be glorified, precisely as occurred in the cases of Joseph and Daniel.
Second, the obscurity of admonitions through dreams serves for exercise. For, once it is known that human beings are accustomed to be moved by God and by created spirits, good and evil, in various modes and by various affections, they may have occasion to act more circumspectly and to provide more cautiously, so that they may perhaps shut out impending evils, may endure them more lightly, or may receive coming goods more abundantly.
Third, the condition of the state of the present life can be a cause. This condition deserved to be distressed by manifold obscurity and perplexity when the first human being fell away from God through his own fault.
Hence blessed Gregory says in Book V of the Moralia: “Cast out from the joys of Paradise and punished with the penalty of blindness, we scarcely apprehend the channels of a whisper, and how thinly and hastily we ponder the marvelous works of God,” and so forth.
Fourth, it can proceed from merit or demerit, or from the indisposition or disposition of the recipient. On account of these things, God forewarns some persons through no sending of dreams; some through ambiguous, unexpected passions of sadness or joy; and some through clear dreams or revelations.
These things are from Henry in the place cited above.