There are many  monsters in the Bible: Leviathan, Behemoth, the basilisk, mermen, unicorns, giants, and dwarves. They fall into the category of cryptozoology—creatures of legend, myth, and lore—and I wonder sometimes if the Bible isn’t poorer since our translators did away with these potentially embarrassing nouns.
In Psalm 104, for example, Leviathan is imagined as a playful part of God’s wondrous creation, while Leviathan is seen in Psalm 74 as an adversary to the creator.  This challenged me. I began to wonder if sin was possible among God’s nonhuman creation—the fall of the Cryptids, for example—a tragedy among mythological types. Leviathan, I reasoned, couldn’t be wholly evil, for God created nothing evil. So if Leviathan (by the way, they seemed to be a species of creature rather than just one monstrous creation) were the adversary of God, they must have fallen from a great height. They were not malicious creatures, but unfortunate ones who made themselves miserable in their rebellion and now sought to make humans miserable as well.
Over the years I have found there to be incredible artistry in the Genesis account of God creating Leviathan (tannin, literally “the great sea monsters”). The vernacular used in this passage of the Bible is closely associated with the legend of Prince yam, the chaos monster who fought Ba’al for supremacy in heaven. Here, though, the tannin is no chaos monster, but part of God’s good and well-ordered creation.
The biblical writers often represented Israel’s enemies as terrifying beasts. Egypt, for example, was often portrayed as a chaos monster whom God defeated by means of the Exodus. In Psalm 89 we read that God crushed the haughty Rahab (a chaos-serpent, another name for Leviathan), and in Isaiah 51 the prophet recalls God’s deliverance of Israel from Egypt in terms of a victorious battle against Rahab and yam, written in hopes of rousing God to defend Israel against their new enemy, Babylon.
And, of course, Leviathan is not the only cryptozoological being in scripture. In the book of Job, Leviathan has a close companion known as Behemoth. The Behemoth in Job likely refers to a hippopotamus, though it’s easy to understand why previous generations have ascribed mythical traits to this abnormal brute.
Leviathan and Behemoth…act as living billboards for God’s sublime creativity and awe-inspiring authority. The giant creatures are not opposed to God, but represent the more chaotic and frightening visage of God.
Stephen Asma, 20th Century biblical scholar
Here are some of the other biblical monsters: A basilisk had the body of a snake, the head and wings of a rooster, two to eight birdlike legs, and killed people merely by looking at them.
…out of the serpent’s root shall come forth a basilisk (cockatrice), and his fruit shall be a fiery flying serpent.
Isaiah 14.29, KVJ (1611)
Until the middle ages, during which time the existence of actual unicorns was officially debunked, the ‘singlehorn’ mentioned in the hebrew Bible was popularly conceived as a unicorn. Only later, when the dubious existence of a horse or goat-like creature with a long horn and possessing magical powers was finally put to rest, did these passages come under closer scrutiny. The popular, scholarly, opinion is that the singlehorn (re’em) mentioned in the scriptures was a rhinoceros.
God brought them out of Egypt. he has as though the glory of a re’em (literally. ‘singlehorn’, Greek monokeros).
Numbers 23.22
In Leviticus, another mythical creature appears, as we read about what can only be merfolk:
And everything that does not have scales in the seas and in the streams—from all that swarms in the water, and from all the living souls (nefesh ha-chayah) in the water—they are an abomination to you.
Leviticus 11.10
Nefesh ha-chayah means, literally, “the soul of the animal of the sea.” Rabbinical commentators (among them Rabbi Avraham ben David and Rabbi Tzvi hirsch Rappaport) consider this to be evidence of a mermaid, being similar to a fish, with scales close to its tail, and with long arms and the form of a person.
Giants also appear in several places throughout the first Testament, most notably Goliath (1 Samuel 17.4-7), Og (Deuteronomy 3.11), the Anakim (Numbers 13.32-33), and the Rephaim (Deuteronomy 2.10-11).
Dwarves, or gammadin (hebrew, see Ezekiel 27.11), were tribal archers from the regions next to Palestine, and were thought to grow only as large as five feet, though some were as diminutive as eighteen inches. how the rabbinical community arrived at this consensus seems confusing, but in Judges 3.16, Ehud is noted as having a dagger in proportion to the length of a gammedin (“of a gomed length”) and that dagger fit beneath his right thigh. So either Ehud was a sizeable giant, or the gammedin were very small.
Scripture even describes episodes of human-animal transmogrification.
King Nebuchadnezzar, for example, is recorded as turning into a wild animal in Daniel 4.30, and many medieval scholars considered this to be a kind of lycanthropy—meaning, Nebuchadnezzar was a werewolf. While such a belief would be totally outlandish today, back then it was far more commonplace. Though some likely interpreted this passage as a reference to a kind of mental illness, others literally believed be became a wild beast.
There is also mention of a phoenix (hebrew chol) in the book of Job. The Midrash contains a discussion about Eve feeding the domesticated and wild animals from the Tree of Knowledge, and all the birds accepted this food except the chol who, according to Rabbi yuden,  had no need of long life because the chol lives for a thousand years anyway, before it finally withers into a heap no larger than an egg. From this heap eventually grow new limbs, and the chol lives again (Midrash Bereishis Rabbah 19.5).
I would say, in my nest I shall expire, and as the chol, increase my days.
Job 29.18
The righteous shall bloom like the phoenix.
Psalm 92.13 LXX, trans.
There are also plenty of composite beings—or griffins—in the Bible:
In my vision at night I looked, and there before me were the four winds of heaven churning up the great sea. four  great beasts, each different from the others, came up out of the sea. The first was like a lion, and it had the wings of an eagle. I watched until its wings were torn off and it was lifted from the ground so that it stood on two feet like a man, and the heart of a man was given to it. And there before me was a second beast, which looked like a bear. It was raised up on one of its sides, and it had three ribs in its mouth between its teeth. It was told, ‘Get up and eat your fill of flesh!’ After that, I looked, and there before me was another beast, one that looked like a leopard. And on its back it had four wings like those of a bird. This beast had four heads, and it was given authority to rule. After that, in my vision at night I looked, and there before me was a fourth beast—terrifying and frightening and very powerful. It had large iron teeth; it crushed and devoured its victims and trampled underfoot whatever was left. It was different from all the former beasts, and it had ten horns.
Daniel 7.2-7
Dragons, called ‘fiery flying serpents,’ are mentioned in Isaiah 14.29 and Isaiah 30.6, just as they figure predominantly in John’s description of the Apocalypse (more on that in a later section).
The nephilim, or grigori (literally “the watchers”) are those sons of God who mated with the daughters of men (see Genesis 6.1-4). for many thousands of years interpreters have understood this to mean that fallen angels came and impregnated human women, giving birth to giants and monsters. Enoch, an apocryphal author considered to be authoritative in Jewish mystical literature, held that it was the destruction of these angel-human hybrids that occasioned the great flood in Genesis 6 and not the sins of humanity at all.
As I survey all of this incredible material, a veritable compendium of monsters from within the pages of scripture, I cannot help but wonder what sense we are to make of it.
What are we supposed to do with all these creatures that had real impact upon the biblical world and the biblical characters? If you believe, as I do, that all scripture is useful for teaching and training in righteousness (see 2 Timothy 3.16), then what possible use are we to make of these monstrosities?
What can we learn from people who were scared of things that aren’t real?
There is a word, unheimlich, that comes to mind here. It is a term first coined by Sigmund freud  and literally means “unhomely” or “uncanny.” Heimlich refers to that which belongs inside the four walls of our home, so unheimlich refers to the fear that our home is not safe, that our sanctuary has been compromised. This is the root of all fears concerning things that go bump in the night. This is the root of our paranoia, our exposure, and our shame.
Monsters are personifications of the unheimlich— they stand for what endangers our sense of safety at home, our sense of stability, integrity, security, well-being, health, and meaning. They make us feel not at home while at home.
This is why so many scary movies involve people being attacked at home. for example, in the beginning of Scream, a babysitter is taunted by a serial killer who is calling her from within her own house. This is also why we find such comfort in the inability of vampires to cross a threshold without an invitation. We know we’re safe at home, so long as we don’t invite the devil in for tea. We are terrified of what might be out there—monsters, giants, and killers—even if they aren’t real. We supply ourselves with ample horror without any help from the real world.
And so it is crucial that we remember that what’s “out there” is less significant that what lives inside.