In Exodus 24:1 (NASB)
Then He said to Moses, “Come up to the Lord, you and Aaron, Nadab and Abihu, and seventy of the elders of Israel, and you shall worship at a distance.
This triggered Genesis 46:27 and Exodus 1:5 (NASB)
All the people who descended from Jacob were seventy people, but Joseph was already in Egypt.
What's the significance of the number 70?
Yes, by jewish tradition, 70 is the number of all nations -- in Babel, the one language was confused into 70 languages, and there are 70 bulls offered on behalf of all nations at the Feast of Tabernacles. In this sense, 70 can be a number meaning "all" or "all the peoples". Here are some citations with references.
Edersheim, contrasting the 70 missionaries and the twelve apostles:
Even these two numbers, as well as the difference in the functions of the two classes of messengers, seem to indicate that the Twelve symbolised the princes of the tribes of Israel, while the Seventy were the symbolical representatives of these tribes, like the seventy elders appointed to assist Moses. 1 This symbolical meaning of the number Seventy continued among the Jews. We can trace it in the LXX. (supposed) translators of the Bible into Greek, and in the seventy members of the Sanhedrin, or supreme court
Edersheim, A. (1896). The Life and Times of Jesus the Messiah (Vol. 2, p. 136). New York: Longmans, Green, and Co.
7. Then the Lord said to the seventy angels that stand before him: “Come then, let us go down, and confuse their language there, so that they will not understand one another’s language.” 8. The Memra of the Lord was revealed against the city, and with it seventy angels corresponding to seventy nations, each having the language of his people and the characters of its writing in his hand. He scattered them thence upon the face of all the earth into seventy languages, so that one did not know what the other said, and they killed one another. And they stopped building the city. 9. That is why it was called Babel, because there the Lord confused the language of all the inhabitants of the earth; and from there the Lord scattered them upon the face of the whole earth.
Cathcart, K., Maher, M., & McNamara, M. (Eds.). (1992). The Aramaic BibleB: Targum Pseudo-Jonathan: Genesis. (M. Maher, Trans.) (Vol. 1, Ge 11:7–9). Collegeville, MN: The Liturgical Press.
Other uses of 70:
Daniel 9.24: "Seventy weeks are decreed upon your people and upon your holy city."
the 70 bullocks of Tabernacles:
XLV. MISHNAH-TRACTATE SUKKAH 5:6 A. ON THE FIRST FESTIVAL DAY OF THE FESTIVAL THERE WERE THIRTEEN BULLOCKS, TWO RAMS, AND ONE GOAT [NUM. 29:13, 16]. THEREREMAINED FOURTEEN LAMBS FOR THE EIGHT PRIESTLY WATCHES. ON THE FIRST DAY, SIX OFFER TWO EACH, AND THE REMAINING TWO, ONE EACH. ON THE SECOND DAY, FIVE OFFER TWO EACH, AND THE REST, ONE EACH. ON THE THIRD DAY, FOUR OFFER TWO EACH, AND THE REST, ONE EACH. ON THE FOURTH DAY, THREE OFFER TWO EACH, AND THE REST OFFER ONE EACH. ON THE FIFTH DAY, TWO OFFER TWO EACH, AND THE REST OFFER ONE EACH. ON THE SIXTH DAY, ONE OFFERS TWO, AND THE REST OFFER ONE EACH. ON THE SEVENTH, ALL OF THEM ARE EQUAL. ON THE EIGHTH, THEY GO BACK TO DRAWING LOTS, AS ON THE [OTHER] FESTIVALS. THEY RULED: “WHOEVER OFFERED A BULLOCK ONE DAY SHOULD NOT OFFER ONE THE NEXT DAY. BUT THEY OFFER THEM IN ROTATION.” 1. I:1: may we say that the Mishnah at hand accords with the view of Rabbi and not of rabbis vis à vis Rabbi? 2. I:2: Continuation of foregoing. 3. I:3: What do these seventy bullocks [listed in the above catalogue] stand for? “They stand for the seventy nations. What does the single bullock [of the Eighth Day] stand for? It stands for the singular nation.
Neusner, J. (2011). The Babylonian Talmud: A Translation and Commentary (Vol. 5b, p. 283). Peabody, MA: Hendrickson Publishers.
Here is JPS commentary describing how the "70" descendents of Jacob is another type for "all":
seventy This harks back to Genesis 46:8–27, which lists all the male descendants of Jacob through his wives and handmaids as follows: Leah 33 + Zilpah 16 + Rachel 14 + Bilhah 7 = 70. However, that total includes Judah’s sons Er and Onan, who died in Canaan, as well as Joseph and his two sons, Manasseh and Ephraim, who were already in Egypt. The list there specifies that “all the persons belonging to Jacob who came to Egypt—his own issue, aside from the wives of Jacob’s sons—all these persons numbered 66.… Thus the total of Jacob’s household who came to Egypt was 70 persons.” Clearly, seventy here is a round number. Deuteronomy 10:22 repeats the same figure: “Your ancestors went down to Egypt seventy persons in all.” This context seems to include Jacob and Joseph but would certainly exclude Ephraim and Manasseh. It does not include Jacob’s daughters-in-law and granddaughters. The number seventy in the Bible is usually meant to be taken as typological, not literal; that is, it is used for the rhetorical effect of evoking the idea of totality, of comprehensiveness on a large scale. Thus, in Genesis 10 precisely seventy nations issue from the three sons of Noah, and these constitute the entire human family. Sarna, N. M. (1991). Exodus (p. 4). Philadelphia: Jewish Publication Society.
70 year exile in Babylon, also signifying totality (e.g. most are still in Babylon, in a spiritual sense)
70 names written on the rod of Moses (e.g. All the names of the elders): As for the rod in With the rod of God in my hand (Exod. 17:9), it is the one with God’s seventy names emblazoned upon it.
Braude, W. G., & Kapstein, I. J. (2002). Pĕsiḳta dĕ-Rab Kahăna: R. Kahana’s compilation of discourses for Sabbaths and festal days (2nd ed., p. 55). Philadephia, PA: Jewish Publication Society.
Psalm 90.10 Year of man is 70 years (e.g. the full allotment to man of years)
An Ephah (or bushel) was defined as the amount of space needed to carry approximately 70 eggs :). Ephah
Braude, W. G., & Kapstein, I. J. (2002). Pĕsiḳta dĕ-Rab Kahăna: R. Kahana’s compilation of discourses for Sabbaths and festal days (2nd ed., p. 671). Philadephia, PA: Jewish Publication Society.
[IF HE SAID,] “LO, I AM A NAZIR WHEN A SON WILL BE BORN TO ME AND A NAZIR FOR A HUNDRED DAYS,” [IF] A SON WAS BORN TO HIM BEFORE SEVENTY DAYS [HAD PASSED], HE HAS LOST NOTHING. [IF THE SON WAS BORN] AFTER SEVENTY DAYS, HE LOSES THE SEVENTY DAYS HE HAS OBSERVED, FOR THERE IS NO CUTTING OF HAIR IN LESS THAN THIRTY DAYS [FROM THE BEGINNING OF THE OBSERVANCE OF THE VOW].
Neusner, J. (2008). The Jerusalem Talmud: A Translation and Commentary. Peabody, Massachusetts: Hendrickson Publishers.
I.16 A. Said R. Simeon b. Laqish, “Whoever is careful about the requirement of show fringes will in response enjoy the merit that two thousand eight hundred slaves will serve him: ‘Thus says the Lord of hosts, in those days it shall come to pass that ten men shall take hold, out of all the languages of the nations, shall even take hold of the skirt of him who is a Jew, saying, we will go with you’ (Zech. 8:23).” [The skirt is the fringe, there are four, and there are seventy languages, hence seventy languages times ten men times four corners, or 2800 (Freedman).
Neusner, J. (2011). The Babylonian Talmud: A Tra nslation and Commentary (Vol. 2, p. 136). Peabody, MA: Hendrickson Publishers.
Giving an allegorical interpretation to the silver basins weighing seventy shekels which were offered by the tribal chiefs at the Tabernacle (Nm 7), the Yalkut Shimoni says:
This corresponds to the seventy names of God, to the seventy names of Israel, to the seventy names of the Law, to the seventy names of Jerusalem.
Now according to the rabbis, these seventy names of God represent the seventy nations descended from Adam, each of which in its own way acknowledges God. We find in the same book:
Israel has seventy names which correspond to the seventy names of God, as it is written: “The praise of You, God, like Your name, reaches to the ends of the earth.” (Ps 48:11)
This is equivalent to saying that there are as many names of God as there are peoples on the earth, and that it is the same supreme God who is worshiped under these different names. Particularly if we consider that this number of seventy divine names does not correspond to anything else in Judaism, it is clear that no other interpretation is possible.
Benamozegh, E. (1995). Elijah Benamozegh: Israel and Humanity. (M. Luria & B. McGinn, Eds., M. Luria, Trans.) (pp. 112–113). New York; Mahwah, NJ: Paulist Press.
Wail, ships of Tarshish! For your fortress is destroyed. And this will happen on that day: And Tyre will be forgotten seventy years, like the days of one king. At the end of seventy years, it will be for Tyre like the song of the prostitute: “Take a harp, go around the city, forgotten prostitute! Do it well, playing a stringed instrument! Make numerous songs, that you may be remembered.” And this shall happen: at the end of seventy years, Yahweh will visit Tyre, and she will return to her harlot’s wages, and she will commit fornication with all the kingdoms of the world on the face of the earth. And this shall happen: her merchandise and her harlot’s wages will be set apart for Yahweh; it will not be stored up, and it will not be hoarded, but her merchandise will be for those who live before the presence of Yahweh, for eating to satiation and for fine clothing.
We are to forgive our brother seventy times seven times -- a reference to the time allotted to Israel to repent before the destruction of the Temple as given in Daniel's prophecy as well as to the general idea of the fullness of forgiveness -- e.g. seventy = all.
Babylonian Talmud has extensive - to the point of painful - discussions on Moses and the 70 judges. Here is a small excerpt.
FF. THE GREAT SANHEDRIN WAS MADE UP OF SEVENTY-ONE MEMBERS, AND THE SMALL ONE WAS TWENTY-THREE. 1. XXX:1: What is the reason for the position of rabbis who hold that it was seventy-one, as against Judah, who saysthat it was only seventy, for they say that Moses was in addition to them M. 1:6E? 2. XXX:2: Our rabbis have taught on Tannaite authority. “But there remained two men in the camp” (Num. 11:26). But there are those who say, “Their names, Eldad’s and Medad’s remained in the urn. For when the Holy One, blessed be he, said to Moses, “Gather to me seventy of the elders of Israel” (Num. 11:16), Moses thought to himself, “How shall I do it? If I choose six from each of the twelve tribes, there will be two extra. If I choose five from each tribe, there will be ten too few. If I choose six from one tribe and five from another, I shall cause jealousy among the tribes.” 3. XXX:3: R. Simeon says, “They remained in the camp. When the Holy One blessed be he said to Moses, ‘Gather for me seventy men’ (Num. 11:16), Eldad and Medad said, ‘We are not worthy of that high position.’ Said the Holy One, blessed be he, ‘Since you diminished yourselves, lo, I shall add greatness to your greatness.’ ” Neusner, J. (2011). The Babylonian Talmud: A Translation and Commentary (Vol. 16, p. 631). Peabody, MA: Hendrickson Publishers.
etc. Many more references of 70 if you dig around, most can be traced to some notion of "all" "completeness" "universal"
The number 70 occurs in a range of contexts such as:
... and so forth. The word "seventy" appears 91 times in the OT and enumerates numerous diverse things. I think it is a round number that simply numbers various things and we should not seek significance where no significance is given.
The Number 70
The number seventy represents heavenly and earthly perfection, the number 70 represents multiple of 7X10. The number 10 denotes fullness, hence the 10 plagues express God's Judgment on Egypt. The "Ten Words"(Commandments), the beast with the Ten horns, Daniel 7: 20,24. Rev. 12:3, 13:1, and Rev. 2:10, God allows his servants to fully tested.
Genesis 46:26-27 (NASB)
26 All the people belonging to Jacob, who came to Egypt, [a]his direct descendants, not including the wives of Jacob’s sons, were sixty-six persons in all, 27 and the sons of Joseph, who were born to him in Egypt, were [b]two; all the people of the house of Jacob, who came to Egypt, were seventy.
Jesus sents 70 disciples to preach.
Luke 10 (YLT)
10 And after these things, the Lord did appoint also other seventy, and sent them by twos before his face, to every city and place whither he himself was about to come,
The Lord said to Moses "Gather me, seventy men......Numbers 11:16
Exodus 24:1 (NASB)
24 Then He said to Moses, “Come up to the Lord, you and Aaron, Nadab and Abihu, and seventy of the elders of Israel, and you shall worship at a distance.
Desolation of Jerusalem ---seventy years
Jeremiah 25:11 (NET Bible) (Read 8-11)
11 This whole area[l] will become a desolate wasteland. These nations will be subject to the king of Babylon for seventy years.’[m]
Seventy-seven--equivalent to without limit
Matthew 18:21-22 (NASB)
Forgiveness
21 Then Peter came up and said to Him, “Lord, how many times shall my brother sin against me and I still forgive him? Up to seven times?” 22 Jesus *said to him, “I do not say to you, up to seven times, but up to [a]seventy-seven times.
Revelation 2:10 (NET Bible)
10 Do not be afraid of the things you are about to suffer. The devil is about to have some of you thrown[a] into prison so you may be tested,[b] and you will experience suffering[c] for ten days. Remain faithful even to the point of death, and I will give you the crown that is life itself.[d]
In the ancient festival, 70 bulls were offered. (Numbers 29:12-34) Hence, the sacrifice of Jesus will benefit faithful ones from all 70 families of mankind that descended from Noah. (Genesis 10:1-29)
