12 Tribes, 12 Apostles, 70 Elders, 70 Disciples, 70 Bulls, 70 Nations, 1 Mixed Multitude
And a mixed multitude went up also with them; and flocks, and herds, even very much cattle. – Exd. 12:38
Also it is worth noting that during Sukkot (Feast of Tabernacles) 70 bulls were sacrificed on behalf of the 70 Nations.
“Regretfully, many in the Christian churches tend to dismiss this celebration as "just another Jewish holiday." This day is a day in which there were sacrifice offerings in the Temple for each of the Gentile nations. According to the Rabbis, there were 70 Gentile nations in ancient times. Beginning in Numbers 29:13, you can read about the sacrifices that were offered on each of the days of Sukkot. On the first day, 13 bullocks were offered as a burnt offering. On the second day, 12 bullocks, on the third day, 11 bullocks, until finally on the seventh day, only 7 bullocks were offered, making a total of 70 bullocks-one for each of the Gentile nations.” – Rick Aharon Chaimberlin, Litt. D. “Sukkot: Feast of Tabernacles”
“This concept of focusing on the positives of others is also learned from the order of sacrifices that is brought on Sukkot. Throughout the holiday, we bring 70 sacrifices, corresponding to the 70 nations of the world. (The Torah views the nations of the world as 70 roots with many other nations as branches.) This is because we see all nations of the world as important. Each has a specific role to fulfill in God's world and we pray to God, through these offerings, that He inspire them to true service of Him. It is especially on Sukkot that we do this because, as mentioned, it is called "The Season of Rejoicing." When we are happy with ourselves, we look at the world positively and can see good in others, even other nations, even if those nations are presently our enemies.” – Rabbi Baruch Leff