To understand why Jeremiah 32:40 addresses the New Covenant, and not the Old Covenant, and why scholars recognize this, it is helpful to consider precisely what each of these covenants really is.
The New Covenant
The "New Covenant" has other names: the "everlasting covenant," "perpetual covenant," and "covenant of peace" are referenced in the Bible, and the "Noahic Covenant" and the "Abrahamic Covenant" also refer to this covenant.
The only covenant which God makes with us is called the New Covenant. It is God's "everlasting covenant" or "perpetual covenant."
The "everlasting covenant"
God speaks of His "everlasting covenant" with the following entities:
- Noah (Genesis 9:16)
- Abraham (Genesis 17:7,13,19)
- The children of Israel (Leviticus 24:8; cf. 1 Chronicles 16:17)
- David (2 Samuel 23:5)
- Jerusalem (Ezekiel 16:60)
The "perpetual covenant" is mentioned in both Exodus and in Jeremiah (see Exodus 31:16 and Jeremiah 50:5).
God speaks of this covenant as His covenant.
And God heard their groaning, and God remembered his covenant with
Abraham, with Isaac, and with Jacob. (Exodus 2:24, KJV)
And God's covenant is as everlasting as He is, for He does not change.
For I am the LORD, I change not; therefore ye sons of Jacob are not
consumed. (Malachi 3:6, KJV)
The New Covenant is the only covenant of salvation offered to us, and it applies to people of all ages, both of the Old Testament times and of our present time.
The "Old" Covenant
The "Old Covenant," on the other hand, is not God's covenant--it is the one we tried to make with God, but failed, and broke it.
In the KJV, the only verse of the Bible in which both the words "old" and "covenant" appear in the same verse, is Hebrews 8:13.
In that he saith, A new covenant, he hath made the first old. Now that
which decayeth and waxeth old is ready to vanish away. (Hebrews 8:13,
Jeremiah Contrasts the Two Covenants
In Jeremiah, the language used indicates this is also the New Covenant. Just the chapter before the verse in question, Jeremiah expressly mentions the New Covenant.
Behold, the days come, saith the LORD, that I will make a new
covenant with the house of Israel, and with the house of Judah:
(Jeremiah 31:31, KJV)
This is followed by distinguishing between this "new covenant" and the other one.
32Not according to the covenant that I made with their fathers in the
day that I took them by the hand to bring them out of the land of
Egypt; which my covenant they brake, although I was an husband
unto them, saith the LORD: 33But this shall be the covenant that I will make with the house of Israel; After those days, saith the LORD, I will put my law in their inward parts, and write it in their hearts; and will be their God, and they shall be my people. 34And they shall teach no more every man his neighbour, and every man his brother, saying, Know the LORD: for they shall all know me, from the least of them unto the greatest of them, saith the LORD: for I will forgive their iniquity, and I will remember their sin no more. (Jeremiah 31:32-34, KJV)
In God's "new" covenant, He promises to write His law in our hearts, to be our God, and to forgive and forget our sins. This is God's everlasting covenant--the only covenant by which we are saved.
The Broken Covenant
What, then, was this broken covenant?
The text tells us who broke it--and it was not God, it was us.
7And Moses came and called for the elders of the people,
and laid before their faces all these words which the LORD commanded
him. 8And all the people answered together, and said, All
that the LORD hath spoken we will do. And Moses returned the words of
the people unto the LORD. (Exodus 19:7-8, KJV)
The people made a promise to God that they did not keep. Indeed, in human strength alone, it is impossible to keep such a promise. This "old covenant" is sometimes also called the Sinaitic covenant, because it was at Mount Sinai where the people made this promise.
Whose covenant is this?
And I will make an everlasting covenant with them, that I will not
turn away from them, to do them good; but I will put my fear in their
hearts, that they shall not depart from me. (Jeremiah 32:40, KJV)
This speaks clearly of the "everlasting covenant," which is God's covenant with us, and the language of the verse shows that this aligns with His "new" covenant.
There are two covenants in the Bible: God's covenant with us, and our covenant with God. God's covenant is the "new" covenant--the one God continually renews with us. The "old" covenant is the one where we try to promise obedience to God, and, attempting in our own strength, fail to keep our promise.
That Jeremiah 32:40 is addressing God's covenant, not ours, is clear both from the language of the verse, and from the context of the "new covenant" being expressly mentioned in the prior chapter.