Midrasch zu Jirmejahu 3:18

Another interpretation (of Deut. 29:9 [10]): YOU ARE STANDING TODAY <ALL OF YOU>. Just as TODAY (literally: THE DAY) sometimes darkens and sometimes lightens, so it is with you. Although you have darkness, the Holy One is going to shine on you with light eternal, as stated (in Is. 60:19): FOR THE LORD SHALL BE YOUR EVERLASTING LIGHT. When? When you all become one group, as stated (in Deut. 4:4): [BUT YOU WHO CLUNG TO THE LORD YOUR GOD] ARE ALL ALIVE TODAY. According to universal custom, if one takes a group of reeds, will he be able to break them at one stroke! But if he takes them one by one, even an infant can break them. So also you find that Israel was not redeemed until they became one group, as stated (in Jer. 50:4): IN THOSE DAYS AND AT THAT TIME, SAYS THE LORD, THE CHILDREN OF ISRAEL, THEY AND THE CHILDREN OF JUDAH, SHALL COME TOGETHER. It also says (In Jer. 3:18): [IN THOSE DAYS] THE HOUSE OF JUDAH SHALL GO WITH THE HOUSE OF ISRAEL, AND THEY SHALL COME TOGETHER FROM THE LAND OF THE NORTH. When they are united, they shall welcome the face of the Divine Presence.

(1) "When you come to the land of your dwellings": What is the halacha of how many things a person is obligated to do for his son? Our rabbis taught: A person is obligated to do five things for his son. G-d can be compared to a father and the Jewish people to His son. Just like a father is obligated to circumcise his son, G-d did so for the Jews by circumcising them by the hand of Yehoshua as it says (Joshua 5:2) "Make for yourself stone knives." A father is obligated to redeem his son [if he is a firstborn] and G-d redeemed the Jews, as it says [II Samuel 7:23) "to redeem it as a nation." [A father is obligated] to teach [his son] Torah, [and] G-d taught the Jews Torah as it says (Deuteronomy 11:19) "Teach them to your children" and it is written "I am G-d your teacher." [A father is obligated] to teach [his son] mitsvot, [and] G-d taught the mitsvot to the Jews. [A father is obligated] to marry [his son] to a woman, [and] G-d told mankind: "Be fruitful and multiply." A father is obligated to his son [in the following ways]: to give him food and drink, to bathe him, to give him ointments, and to clothe him, and thus did G-d for the Jews, as it is written (Ezekiel 16: 9) "And I washed you in water, and I washed away your blood...and I clothed you with embroidered clothing...and My bread which I gave you..." [and in Numbers 21:17] "Arise, o well, sing to it." What does a father give to a son? Possessions. Thus G-d did for the Jews, as it says in Jeremiah 3:18, "And I gave you a beloved land." And what must a son give to his father? A gift. Thus G-d said to the Jews, "When you come to the land...and bring an olah-offering to G-d."