Not all the time they aren't. Here are some examples of symbols that we clearly take AS symbols, but are not explained as such:
In his right hand he held seven stars, from his mouth came a sharp two-edged sword, and his face was like the sun shining in full strength. - Revelation 1:16
Clearly people realize that Christ doesn't have a dirty great sword coming from his mouth. It is his word, his word of truth that will cut, sharper than a two edged sword, that proceeds from his mouth, that this is talking about. And yet it doesn't state this. It is assumed it by symbol.
And one of the elders said to me, “Weep no more; behold, the Lion of the tribe of Judah, the Root of David, has conquered, so that he can open the scroll and its seven seals.” And between the throne and the four living creatures and among the elders I saw a Lamb standing, as though it had been slain, with seven horns and with seven eyes, which are the seven spirits of God sent out into all the earth. - Revelation 5:5–6
Again, we know that it is neither a Lion, or a Lamb that was actually seen. John see's Christ, victorious in his role as Lion, but standing as though slain, proving that his victory came through his sacrifice. Vivid symbolism!
Now I watched when the Lamb opened one of the seven seals, and I heard one of the four living creatures say with a voice like thunder, “Come!” And I looked, and behold, a white horse! And its rider had a bow, and a crown was given to him, and he came out conquering, and to conquer. When he opened the second seal, I heard the second living creature say, “Come!” And out came another horse, bright red. Its rider was permitted to take peace from the earth, so that people should slay one another, and he was given a great sword.
When he opened the third seal, I heard the third living creature say, “Come!” And I looked, and behold, a black horse! And its rider had a pair of scales in his hand. And I heard what seemed to be a voice in the midst of the four living creatures, saying, “A quart of wheat for a denarius, and three quarts of barley for a denarius, and do not harm the oil and wine!” When he opened the fourth seal, I heard the voice of the fourth living creature say, “Come!” And I looked, and behold, a pale horse! And its rider's name was Death, and Hades followed him. And they were given authority over a fourth of the earth, to kill with sword and with famine and with pestilence and by wild beasts of the earth. - Revelation 6:1–8
Are readers to assume that actual horses and actual riders are to come forth? No, we automatically understand that these horses and riders symbolize things that are going to happen. The white horse symbolizes global unification under a leader or government, the red horse global war and destruction. The next two horses follows those two; the black shows famine and scarcity and the pale horse death and disease. We know that these 'riders and horses' are not really riders upon horses but states that will come upon the world. No one debates that.
And a great sign appeared in heaven: a woman clothed with the sun, with the moon under her feet, and on her head a crown of twelve stars. She was pregnant and was crying out in birth pains and the agony of giving birth. And another sign appeared in heaven: behold, a great red dragon, with seven heads and ten horns, and on his heads seven diadems. His tail swept down a third of the stars of heaven and cast them to the earth. And the dragon stood before the woman who was about to give birth, so that when she bore her child he might devour it. She gave birth to a male child, one who is to rule all the nations with a rod of iron, but her child was caught up to God and to his throne, and the woman fled into the wilderness, where she has a place prepared by God, in which she is to be nourished for 1,260 days. - Revelation 12:1–6
This passage is chock full of symbolism. The interpretation is often debated, but most people will agree that that woman is Israel, the child Christ, the dragon is clearly Satan. That established, we don't expect to see a literal woman 'clothed with the sun'. I mean...really? It has to be a symbol of something, but we are not told specifically what. A crown of 12 stars? Well, if a star was small enough to fit on a crown, swell...you get my drift...12 stars on a crown? Symbol again. A dragon with 7 heads? No doubt possible for Satan, should he choose, but do we imagine that he actually prowls around like that? And he swept a third of the stars to earth? Do you see how "literally" impossible that act is? If a third of the stars crashed to earth, the earth would be no more.
Look, my point is not to tear to shreds the notion of taking the bible 'literally', because in point of fact, when we take Revelation as Apocalyptic literature, as it is meant to be, we ARE taking it literally. My problem is with taking it literalistically. Trying to force images into a literal framework when clearly they were not meant to be taken that way. But I admire the heart of wanting to take the bible as true and as essential, and needing to stand behind that premise. I think that is spot on. Because it is true, and it is essential, every single word of it. We just need to realize that symbols can show truth just as well, as it does in Daniel, and Revelation.
