Sometimes people ask me if I believe in dreams. At the risk of sounding Clintonian, I usually reply, “It all depends on what you mean by believe.” Do I believe dreams happen? Obviously, yes. Do I believe them significant? Again, yes. But here I add the qualifier “usually”. For the question is, “Just what are they significant of?” Some dreams may be, as Ebenezer Scrooge tells us, signs that we had a bit of bad beef or an underdone potato. Other dreams are, I think, the peculiar mechanism by which that mysterious tangle of soul, mind, body and emotion that I call “me” works through its difficulties and affords me such sanity as I still possess. And still others could be “signs” in the Christian sense: portents, promises, visions, prophecies, and warnings sent by God to guide his servants in their travels through life.
Typically, when people are asking whether I “believe” in dreams, they mean that last definition: supernatural signs from God. I do indeed believe dreams can be significant in that sense, but I generally don't expect them to be. That is because: a) this is the average view of most average Joes (and I tend to think the normal beliefs of normal people have much to recommend them); and b) it is the decided belief of two biblical Joes Joseph, son of Jacob and Joseph, father of Jesus. Both of them were favored with dreams from God himself, yet both they and those around them seemed to recognize such dreams were not a dime a dozen.
Indeed, what is notable in a day and age that took dreams, visions, signs, and portents much more seriously than we do, is how rarely God is reported to have spoken through dreams in Scripture. Jews, like everyone else, dream several times every night and have been doing so by the millions for the past 4,000 years. Yet only a few dreams made it into Scripture. This would seem to indicate that God has other methods of communication he likes better.
My own opinion (and it's only an opinion) is that revelation primarily rooted in dreams would be a revelation that would be easy to dismiss as private, subjective, and hallucinatory. Jesus’ miracles were witnessed not in visions, but on street corners, in crowds, and in full view of gobs of witnesses. Even the Resurrection was seen by 500 people at once. The faith is public, not private.
In addition, I think dreams are the whipped cream with the cherry on top that God periodically adds to the generally more prosaic diet of revelation he gives through Scripture, Tradition, and in the ordinary life, worship, and teaching of the church. God is a God of miracles to be sure. But he is, vastly more often, the God of the ordinary. His most catastrophic, exquisite, and overwhelmingly dramatic revelation to us comes, not in the form of spectacular visions but rather as a flat little bit of something that looks like bread and a sip of something that looks like wine. The most awesome vision presented to our senses is not the sight of the sky being rolled up like a scroll, but our neighbor' s face.
So it is fitting that dreams would be used sparingly by God in revealing himself lest we get the idea that the supernatural life was primarily about special effects and not about loving God and our neighbor. That’s because Jesus knew the way to make dreams come true was to wake people up.