We are still in the tens in chapter five of the Avot; here’s the translation of Judah Goldin:
Ten miracles were wrought for our ancestors in Egypt and ten at the sea. Ten plagues the Holy One, blessed by He, visited on the Egyptians in Egypt, and ten at the sea.
I’m taking verses five and six together here, as opinion seems to be that six is just a rephrasing of five for emphasis. That is, the ten miracles for our ancestors in Egypt were the miraculous immunity from the ten plagues visited on the Egyptians. On the other hand, there are two different stories about the miracles at the sea: for the Israelites, who were reluctant to cross, Moses has to mite the sea ten times:
When our fathers stood by the sea, Moses said to them: "Arise and pass through it!" and they rejoined: "We will not pass, till we see the sea become chips, chips." Whereupon Moses struck the sea with his staff, and it was converted into chips, as it is written [Habakkuk, iii. 14]: "Thou didst strike through with his own spears the chiefs of his villages." Again Moses said to them: "Arise and pass through it," and they rejoined: "We will not pass till the sea becomes a valley." Moses struck the sea again, and it became a valley, as it is written [Ps. lviii. 13]: "He divided the sea, and caused them to pass through"; also [Is. lxiii. 14]: "As a beast goeth down into the valley." Moses again urged them to pass through the sea, and they answered: "We will not, till it becomes separated into parts"; as it is written [Ps. cxxxvi. 13]: "To him who divided the Red Sea into parts." …
And so on and so forth until there are ten of them. As for the Egyptians, they are killed ten times…
These are the TEN plagues at the Sea, TEN kinds of death described by TEN different verbs in the fifteenth chapter of Exodus: hath he thrown (15:2); hath he cast (15:4); deeps cover them (15:5); they went down into the depths (15:5) …
And so on and so forth until there are ten of them.
Digression: Many of y’all are thinking that the Egyptians suffered forty or perhaps fifty plagues at the Red Sea, or perhaps two hundred and fifty, according to the sages at B’nai Barak. This is what happens when you stay up too late. Really, the first thing we should learn from the Talmud is that there are differences of interpretation, and that we can’t let ourselves be tied to one particular interpretation. Anyway, even if the ten were multiplied fourfold, or fivefold, or fivefold and fivefold again, there were ten to be multiplied, and this is a verse about tens. End Digression
So. The world is created through Ten Utterances, then there are Ten Generations before the Flood, then Ten Generations until Abraham, then Ten Trials of Abraham, and now Ten Plagues (and miracles, and ten more of each). And there will be more tens coming up, but this is a good moment, I think, to stop and ask why tens? Which is in some ways unanswerable—in R. Travers Herford’s commentary, his only note on this verse calls it “a pair of Scripture series merely stated and calling for no comment. The compiler, having started on a series of groups of ten, includes in it an observed fact of Scripture. No lesson is drawn from the fact. No lesson? Is it possible that there is a verse of Avot with no lesson?
Here’s the lesson I am drawing at the moment:
Do you know how when you learn about the Fibonacci series, it turns up everywhere? And for a while, all you can think about is how utterly cool it is?
Tolerabimus quod tolerare debemus,
I would think tens are at the very fabric of our being–ten fingers, ten toes. So our biology is our destiny, yes?