Midrash su Cantico dei cantici 6:8

Another interpretation: "Number all the first-born males..." (Numbers 3:40) This is what is written (Song of Songs 6:8-9): "There are threescore queens ... My dove, my undefiled, is but one ..." Compare in parable to a person who had a sales-bundle of glass stones and would bring them them to the market, but would not notice their number, since he would not bring them out by number. He would go in to put them away and would not put them away by number, since he would not care about them, as they were glass. But he had one sales-bundle of precious pearls, and he would take it and bring it out by number and put it away by number. Similarly, so to speak, the Holy One Blessed be He said to the nations of the world, "I have not assigned a number. Why? Because they are not important to me at all. As it says (Isaiah 40:17), 'All the nations are as nothing before Him.' But you are My children, as it says, (Isaiah 46:3), 'that are borne [by Me] from the birth ...' Therefore, I count you all the time." Therefore, it is said "Number all the first-born males." That is: "There are threescore queens ... My dove, my undefiled, is but one ..." - these are Israel.

Another interpretation: "Number all the first-born males..." (Numbers 3:40) This is what is written (Song of Songs 6:8-9): "There are threescore queens ... My dove, my undefiled, is but one ..." Compare in parable to a person who had a sales-bundle of glass stones and would bring them them to the market, but would not notice their number, since he would not bring them out by number. He would go in to put them away and would not put them away by number, since he would not care about them, as they were glass. But he had one sales-bundle of precious pearls, and he would take it and bring it out by number and put it away by number. Similarly, so to speak, the Holy One Blessed be He said to the nations of the world, "I have not assigned a number. Why? Because they are not important to me at all. As it says (Isaiah 40:17), 'All the nations are as nothing before Him.' But you are My children, as it says, (Isaiah 46:3), 'that are borne [by Me] from the birth ...' Therefore, I count you all the time." Therefore, it is said "Number all the first-born males." That is: "There are threescore queens ... My dove, my undefiled, is but one ..." - these are Israel.

“There are sixty queens, and eighty concubines, and young women without number” (Song of Songs 6:8).
“There are sixty queens.” Rabbi Ḥiyya of Tzippori and Rabbi Levi interpreted the verse regarding the nations of the world. Rabbi Ḥiyya said: Sixty and eighty are one hundred and forty. Forty of them have a language [of their own] but do not have a script [of their own] and forty do not have a language but have a script. “And young women without number,” the rest of them have neither a language nor a script. Is the same, perhaps, true of Israel? The verse states: “To the Jews in their language and in their script” (Esther 8:9).
Rabbi Levi said: Sixty and eighty are one hundred and forty. Seventy of them know their fathers but do not know their mothers. Seventy of them know their mothers but do not know their fathers. “And young women without number,” [those] who do not know their fathers or their mothers. Is the same, perhaps, true of Israel? The verse states: “They established their genealogy according to their families, according to their fathers' household” (Numbers 1:18).²⁴The term “their families” indicates that they knew their mothers and “their fathers’ household” indicates they knew their fathers. Alternatively, “they established their genealogy [vayityaldu]” is related to the term birth [leida], indicating that they knew their mothers.