Every number in the Torah has a symbolic meaning, and so, every mention of, say, the number “3” is connected to every other mention of the number “3” (including 30 and 300).
If we assume this is true (if you disagree, please email me and challenge), then why did there have to be ten plagues? What does the number “10” mean in the Torah anyway?
Well… where is the word assar, for “ten” mentioned?
Here are the examples:
(The Flood)The waters went on diminishing until the tenth month; in the tenth month … the tops of the mountains became visible.
In the tenth month, G-d shows salvation! He separates the flood from causing death, giving the world the opportunity for life once again. He blessed humanity and the world.
Avram tithes (“tens”) after he wins the battle against the Kings – in recognition of G-d’s miraculous deliverance in his victory.
Avraham negotiates with G-d over saving Sodom and Gomorrah, but it comes down to whether or not ten righteous men can be found in the city. For Sodom, the number “ten” is the quorum necessary to receive collective blessings.
Yaakov promises to tithe (“ten”) to G-d if Yaakov is delivered, according to the deal struck at Beit El.
Yaakov complains that G-d changed his wages “ten” times – and then his wives tell him: Truly, all the wealth [ten] that God has taken away from our father belongs to us…” (Gen. 31:16)
Ten of Joseph’s brothers went down to get grain rations in Egypt. Was that number used because the brothers were hoping for a divine result like that of the flood or what Sodom could have been?
And then Joseph sends a coded message using the number “ten” back to Jacob!
And to his father he sent the following: ten he-asses laden with the best things of Egypt, and ten she-asses laden with grain, bread, and provisions for his father on the journey. (Gen. 45:23)
In Egypt, the number comes up again:
Speak to the whole community of Israel and say that on the tenth of this month each of them shall take a lamb to a family, a lamb to a household.
Num: 18:21-26 commands us to give “from the ten” of all of our agricultural harvest to the Levites.
And Deuteronomy 14:22-28 contains another tithing commandment, to wit:
You shall consume the tithes [from the tenth] of your new grain and wine and oil, and the firstlings of your herds and flocks, in the presence of the LORD your God … so that you may learn to revere the LORD your God forever.
Looking at the above, is there a clear pattern?
I think so. Ten is connected to the recognition of G-d’s presence, and G-d as the source of all of our blessings. Ten is the number of deliverance!
In which case, the ten plagues would prove to the Egyptians that G-d is in the world. And they prove to the Jewish people that G-d is the sole explanation for all the miracles and plagues that they witness. The number holds meaning for both audiences!