LXX Jeremiah 38:32
31 Behold, the days come, saith the Lord, when I will make a new covenant with the house of Israel, and with the house of Juda: 32 not according to the covenant which I made with their fathers in the day when I took hold of their hand to bring them out of the land of Egypt; for they abode not in my covenant, and I disregarded them, saith the Lord. 33 For this is my covenant which I will make with the house of Israel; after those days, saith the Lord, I will surely put my laws into their mind, and write them on their hearts; and I will be to them a God, and they shall be to me a people. 34 And they shall not at all teach every one his fellow citizen, and every one his brother, saying, Know the Lord: for all shall know me, from the least of them to the greatest of them: for I will be merciful to their iniquities, and their sins I will remember no more. 35 Though the sky should be raised to a greater height, saith the Lord, and though the ground of the earth should be sunk lower beneath, yet I will not cast off the family of Israel, saith the Lord, for all that they have done.
Hebrews 8:9
7 For if that first covenant had been faultless, no one would have looked for a second one. 8 But showing its fault, God says to them, “Look, the days are coming, says the Lord, when I will complete a new covenant with the house of Israel and with the house of Judah. 9 It will not be like the covenant that I made with their fathers, on the day when I took them by the hand to lead them out of Egypt, because they did not continue in my covenant and I had no regard for them, says the Lord. 10 For this is the covenant that I will establish with the house of Israel after those days, says the Lord. I will put my laws in their minds, and I will inscribe them on their hearts. And I will be their God, and they will be my people. 11 And there will be no need at all for each one to teach his countryman or each one to teach his brother saying, ‘Know the Lord,’ since they will all know me, from the least to the greatest. 12 For I will be merciful toward their evil deeds, and their sins I will remember no longer.”
Notes and References
"... Several further echoes of Isaiah 41:10 (LXX) are to be found in Hebrews, too: Israel is urged not to fear (compare Hebrerws 2:15), nor to go astray compare Hebrews 3:10) 'because I have helped you' (compare Hebrews 2:18), the help coming a term which might well have a Christological sense for the author of Hebrews (compare 1:3, 13); the passage also contains the divine promise (41:9, compare Hebrews 13:5) and a reference to the earth as the place from which salvation is needed (41:9). This last unites it with Jeremiah 38:32 (LXX = 31:32 MT), quoted in Hebrews 8:9, in which the Exodus is described as the place of bondage out of which God leads his people. A third passage is also worth quoting: Wisdom exalts her sons, and gives help to those who seek her' (Sirach 4:11), a verse which has much in common with the letter's thought about exaltation, sonship and 'drawing near' to God through Christ (4:16, 7:25) ..."
Dunnill, John Covenant and Sacrifice in the Letter to the Hebrews (pp. 215-216) Cambridge University Press, 1992