The LXX Reading
I do not have access to every possible LXX reading, but what I do have access to is interesting. Their readings of the section in question are as follows (with my as literal word for word as possible translations and bolding paralleling Greek/English words):
n/a (verse is not in it)
H. B. Swete's
n/a (verse is not in it)
n/a (only has parts from ch. 1-2)
L. C. L. Brenton's (Codex Vaticanus is his primary source; but that is not where this verse is coming from, as it would be on 1137 of the mss and it is missing there as well):
Τὰ ἐλέη Κυρίου, ὅτι οὐκ ἐξέλιπέ με, ὅτι οὐ συνετελέσθησαν οἱ οἰκτιρμοὶ αὐτοῦ ...[*]
The mercies of the Lord, that he/it does not fail me, that they do not cease—the compassions of him [less literal order, but better for English reading: "... that the compassions of him do not cease."]
* The Greek of his v.22 continues on, so the whole verse is:
Τὰ ἐλέη Κυρίου, ὅτι οὐκ ἐξέλιπέ με, ὅτι οὐ συνετελέσθησαν οἱ
οἰκτιρμοὶ αὐτοῦ· μῆνας εἰς τὰς πρωΐας ἐλέησον Κύριε, ὅτι οὐ
συνετελέσθημεν, ὅτι οὐ συνετελέσθησαν οἱ οἰκτιρμοὶ αὐτοῦ.
To my knowledge, no major translation renders the latter part (bolded above), but continues with v.23, which is:
Καινὰ εἰς τὰς πρωΐας, πολλὴ ἡ πίστις σου.
New in the morning, great [is] the faithfulness of you.
- The Ziegler apparatus quote that the OP notes is the latter part of the verse in question (i.e. the "parallel" that leads some to favor the emendation based off of that parallelism).
- The ἐξέλιπέ is the aorist (BDAG notes 2nd aorist) 3rd person singular of ἐκλείπω (fail, depart, cease). So the singular means it is not referring back to the plural Τὰ ἐλέη (mercies) directly, but could be referring:
- back to Κυρίου ("he")
- back to the whole phrase ("the mercies of the Lord") as a single grammatical entity
- The object is a 1st person singular με, which does not reflect either Hebrew rendering of the text (MT or emendation).
So if nothing else, the LXX is a poor testimony to base an emendation off of, since many manuscripts apparently do not have the verse, and the one form I have found here has a lot of extra text in the verse that is ignored (and does not match the MT), and what is not ignored does not accurately translate either form the Hebrew is thought to take since it adds the first person object.
However, it is not just the LXX they base this on, but Rick Brannan and Israel Loken in The Lexham Textual Notes on the Bible, Lexham Bible Reference Series (Bellingham, WA: Lexham Press, 2014) state:
Most Hebrew manuscripts read “Because of the loyal love of Yahweh, we
are not cut off” rather than “The loyal love of Yahweh does not
cease.” The latter reading requires an emendation of the Hebrew word;
however, it is supported by the LXX, Syr[iac], and T[argums] and forms a much
better parallel with the following line.
This is more reserved than the NETS note the OP linked to, which in part says:
The MT reads תָמְנוּ (tamnu) “indeed we are [not] cut off,” Qal
perfect 1st person common plural from תָּמַם (tamam, “be finished”):
“[Because of] the kindnesses of the Lord, we are not cut off.”
However, the ancient versions (LXX, Syriac Peshitta, Aramaic Targum)
and many medieval Hebrew mss preserve the alternate reading תָּמּוּ
(tammu), Qal perfect 3rd person common plural from תָּמַם (tamam, “to
be finished”): “The kindnesses of the Lord never cease.” The external
evidence favors the alternate reading. The internal evidence supports
this as well, as the parallel B-line suggests: “his compassions never
come to an end.”
Notice the latter states (emphasis added) "many medieval Hebrew mss preserve the alternate reading," whereas the former quote stated "most Hebrew manuscripts" have the MT reading. Both fail to note that Jerome's Vulgate (4th c.) testifies to the MT reading:
misericordiae Domini quia non sumus consumpti quia non defecerunt miserationes eius
Which Google translate gives as:
the LORD's mercies we are not consumed, because his compassions fail not because they do not
So there are ancient translations testifying to the MT text also.
The Hebrew Text
The MT reads (BHS):
חַֽסְדֵ֤י יְהוָה֙ כִּ֣י לֹא־תָ֔מְנוּ כִּ֥י לֹא־כָל֖וּ רַחֲמָֽיו
The mercies of YHWH, that we are not consumed[*], that His compassions fail not.
* Per HALOT, the word תמם can mean be completed/finished, come to an end/expire/cease, be consumed/burnt out, be worn down/perish.
The controversy does reside, as the OP notes, in the form of the word, since in the MT, the form is 1st person plural and the emendation is 3rd person plural, which is the difference in radicals of the nun before the final letter or not:
תָ֔מְנוּ vs. תָ֔מְּוּ
Recall that ancient texts would not have been pointed, so it would be:
תמנו (MT) vs. תמו (Variant)
Which is correct? Consider that if the MT reading is actually the variant, a scribe would have had to add a letter, the nun, whereas the reverse is the case if the MT reading is the correct form, as the nun would have been dropped in the variant. It seems to me that two things recommend the MT reading in this case:
- As a textual error (rather than deliberate change), it would seem generally easier to miss writing a letter (omission of spelling) than to add a letter (addition to spelling). Whether that is statistically true in erroneous variant spellings, I do not know. I guess it is possible that an exceptionally malformed left side of a mem (מ) in a hand copy might have looked to a later scribe like two letters, a mem-nun combo (מנ), but that seems a stretch for an explanation of an erroneous addition. An omission, however, can simply occur from a break in concentration via a distraction (while either looking at the vorlage or while scribing the copy).
- While I am not typically a blanket advocate for "the more difficult reading" is likely the original reading maxim that many textual critics follow, in this case here, it would seem less likely that a scribe would have erroneously introduced a 1st person plural reference (as the MT has it) into a text where a 3rd plural would also fit. It also would seem unlikely to be a purposeful addition to change it to 1st person for similar reasons. However, that is not to say the 1st person plural does not fit (it is not that difficult of a reading), as the context shows.
In my mind, the context of Lamentations ch. 1-3 up to 3:22 supports the MT reading as much as, if not more so, than the proposed emendation.
- Chapter 1 emphasizes what has happened to Jerusalem
- Chapter 2 emphasizes what has happened to the people of Israel (though still in some context regarding Jerusalem)
- Chapter 3 emphasizes what has happened to the writer specifically (v.1)
All that has happened are extreme trials and hardships to each, yet "we are not consumed" of the MT reading is then a clear statement that God has not fully caused the people of Israel to cease, even despite all that God has righteously brought on them for their sin.
Verses 21-22 are a transition point of speaking about hope.
So there is no reason in the broad context to reject the MT reading.
What of the paralleling within the verse, which is noted as a reason to emend? It is well known that Hebrew parallelism is common; but the MT reading does not destroy parallelism. Indeed, for the MT reading, it keeps both points after the כִּ֣י as parallel in thought (things that do not cease), each of which defines the mercies, whereas the emendation makes the first point only related to the mercies, but the second point simply a restatement of the first. It is either:
- The Lord's mercies = "we" (Israel) and the Lord's compassions do not cease
- The Lord's mercies do not cease and His compassions do not cease
It seems to me #1 is a better paralleling idea, mentioning the two things that do not fail/cease, proving the Lord's mercies. But if so, what role is The Lord's mercies taking? I believe it is a continuation of v.21, that the "this" in "this I recall to mind" is not referring back to the previous verse, but is looking ahead to "The Lord's mercies" of v.22. It is His mercies that the writer is recalling to mind. So he is recalling
The Lord's mercies [are] that we are not consumed, that His compassions do not cease.
This recollection is in context of the great judgment upon them as the previous chapters and verses related (and some following will also). So that they are surviving through all this is by His mercy, and as Lamentations ends, if that mercy should end then all is lost, for Lam 5:21-22 states:
21 Turn us back to You, O LORD, and we will be restored; Renew our days as of old,
22 Unless You have utterly rejected us, And are very angry with us!
It all depends on how one weighs the evidence as to which reading is correct. Both readings do not do any violence to the concepts expressed in Lamentations, and when no reason really exists to emend, I favor the MT on that ground alone. But as I note, there are other grounds that I believe favor keeping the MT reading. Yet obviously, others weight things differently.
The LXX (what readings have it), do seem to support a 3rd person reading, but a singular, not 3rd person plural or 1st person plural as the two Hebrew forms would be.