Hi Jamie,
You ask a good question about creeping things. At a remove of thousands of years, the definitions of words are pretty tricky. So let’s do a little word study together. I’ll learn, too!
The word in Hebrew is רֶמֶשׂ (remes).
I’ll get back to the Hebrew passages in a moment, but I think it’s enlightening to look at the later Greek understandings of the category. The Septuagint translates it with the Greek word ἑρπετῶν (herpetōn). This root is of course where we get “herpetology,” the study of amphibians and reptiles, but that’s an English word so it doesn’t tell us anything. Interestingly, the New Testament uses this Greek word similarly to the way Genesis uses רֶמֶשׂ, as a major taxonomic category of living things. The key verses here are these:
and exchanged the glory of the incorruptible God for an image in the form of corruptible man and of birds and four-footed animals (τετραπόδων) and ἑρπετῶν. (Rom 1:23)
For every species of beasts (θηρίων) and birds, of ἑρπετῶν and creatures of the sea, is tamed and has been tamed by the human race. (James 3:7)
and there were in it [i.e., the great sheet of Peter’s vision] all kinds of four-footed animals and ἑρπετὰ of the earth and birds of the air. (Acts 10:12)
and when I had fixed my gaze on it [again, the great sheet] and was observing it I saw the four-footed animals of the earth and the wild beasts and the ἑρπετὰ and the birds of the air. (Acts 11:6)
In the cultural categories of their times, this was clearly a major subdivision of animals. It doesn’t seem to have a neat one-to-one correspondence with any of our modern English categories.
In Hebrew, for the most part, it seems to do the same thing. It appears this way of course in Genesis 1 (verses 21, 26, 28, and 30) and the Noah story, where the categories mirror Genesis 1 (Gen 7: 8, 14, and 21; 8: 17, 19; 9:2). Apart from that, here’s what we find.
In that day I will also make a covenant for them With the beasts (חַיַּ֤ת, living things) of the field, The birds of the sky And the רֶמֶשׂ of the ground. And I will abolish the bow, the sword and war from the land, And will make them lie down in safety. (Hos 2:18)
So I entered and looked, and behold, every form of רֶמֶשׂ and beasts (בְהֵמָה) and detestable things, with all the idols of the house of Israel, were carved on the wall all around. (Eze 8:10)
The fish of the sea, the birds of the heavens, the beasts (חַיַּ֣ת, living things) of the field, all the רֶמֶשׂ that creep on the earth, and all the men who are on the face of the earth will shake at My presence; the mountains also will be thrown down, the steep pathways will collapse and every wall will fall to the ground. (Eze 38:20)
He [Solomon in his wisdom] spoke of trees, from the cedar that is in Lebanon even to the hyssop that grows on the wall; he spoke also of animals (הַבְּהֵמָ֣ה) and birds and רֶמֶשׂ and fish. (1 Ki 4:33)
Beasts (חַיָּ֥ה, living things) and all cattle (בְּהֵמָ֑ה); and רֶמֶשׂ and winged fowl; [among the many things commanded to praise the Lord] (Ps 148:10)
There are two passages that don’t fit this mold, where רֶמֶשׂ seems to refer to some kind of fish. Of course, words often have several distinct meanings (polysemy), and there might also be different ways of interpreting these bits of passages. But here they are, for completeness’s sake:
24 O LORD, how many are Your works! In wisdom You have made them all; The earth is full of Your possessions. 25 There is the sea, great and broad, In which are רֶמֶשׂ without number, Animals (חַיּ֥וֹת, living things) both small and great. 26 There the ships move along, And Leviathan, which You have formed to sport in it. 27 They all wait for You To give them their food in due season. (Ps 104:24-27; note that Psalm 104 is a psalm of creation)
13b Why are You silent when the wicked swallow up Those more righteous than they? 14 Why have You made men like the fish of the sea, Like רֶמֶשׂ without a ruler over them? 15 The Chaldeans bring all of them up with a hook, Drag them away with their net, And gather them together in their fishing net. Therefore they rejoice and are glad. 16 Therefore they offer a sacrifice to their net And burn incense to their fishing net; Because through these things their catch is large, And their food is plentiful. 17 Will they therefore empty their net And continually slay nations without sparing? (Hab 1:13-17)
These last two passages both seem to connect to the sense of a school of fish that swarms. But I wouldn’t think it would be wise to use these last two passages to read into all the other uses of רֶמֶשׂ.
Summarizing: As a major category of living things, it seems to be frequently played against birds, fish, and beasts. But how would an Ancient Near Easterner define beasts? Multiple words are used (חַיָּ֥ה, בְּהֵמָ֑ה) and I don’t have time for more word study today. We don’t have any science textbooks from the Ancient Near East, so it’s not as if we have a list of what they meant by these words. I suspect further word study won’t resolve this. So does it mean (picking some common creatures that were surely known to the author) snakes? frogs? ants? mice (as you suggested)? I suspect mice is the least likely option and reptiles the most likely, but I have zero proof of this.
…but this is kind of why I think we’re missing the point. The point is not, “So God showed me this one thing in one of the visions he showed me, and I’m going to describe it as a remes.” The point is, “God made all living things, which in my culture includes the categories of bird, beast, livestock, fish, sea monster, and remes.” If we look at what the author was saying in his wider cultural context, we don’t have to do this bizarre sort game of trying to figure out which Linnean taxonomic category the author was trying to convey with each of his ancient words. He wasn’t trying to convey Linnean taxonomies at all. He was describing God as the creator of all living things, and he used all the major categories of life that he knew.
