You keep trying to shift the burden of proof to me when it is all yours. Here is what scripture says.
Jeremiah 13:14 And I will dash them one against another, even the fathers and the sons together, saith the LORD: I will not pity, nor spare, nor have mercy, but destroy them.
God is speaking in this verse, Can you show me any verse where God Himself is speaking, not Paul or some other writer, said about the Israelites He destroyed in Jer 13:14., because they rejected Him, "Oops I changed my mind and now I will have mercy, I will have pity. I will spare and I will undestroy and save them?
If He didn't have pity - as regards the particular judgment in view - of the context - and killed them, how does that address what happens to them postmortem? Does He say that after He destroys/kills them that He will - never - have mercy on them in the afterlife also? Or is the passage completely silent about any postmortem consequences? Does the context even mention "hell"? No. Compare this a few chapters later from the same book & author:
Jeremiah 21:7
"Then afterwards," declares the LORD, "I will give over Zedekiah king of Judah and his servants and the people, even those who survive in this city from the pestilence, the sword and the famine, into the hand of Nebuchadnezzar king of Babylon, and into the hand of their foes and into the hand of those who seek their lives; and he will strike them down with the edge of the sword. He will not spare them nor have pity nor compassion."
Which proves the "not sparing" & not "having pity" is related to this life only and the particular judgement in view - in the context - i.e. being killed..."he will strike them down with the edge of the sword". It has nothing to do with anything beyond this life, or postmortem consequences.
Show me where that quote or context says after He destroyed them, i.e. killed their body, that He would also never have mercy on their - souls - postmortem. If you can't do that, then as far as opposing universalism your verse fails with all the other lame attempts to oppose universalism & is discarded into the trash can of failed attempts to oppose universalism.
Nowhere in Scripture does it say those destroyed (i.e. killed) cannot be saved postmortem. Or that they cannot receive correction and mercy postmortem. 1 Cor.5:4-5 says destruction is for salvation. And Mt.1:21 + 2:6; Rom.11:26; Isa.45:21-25 all Israel shall be saved.
Many scriptures show God's punishments in this life are corrective & there's nothing in the Bible saying that He suddenly changes His ways in that regard postmortem.
Hab.1:12 O LORD my God, my Holy One, you who are eternal--surely you do not plan to wipe us out? O LORD, our Rock, you have sent these Babylonians to correct us, to punish us for our many sins.
Because I have sinned against him, I will bear the LORD’s wrath, until he pleads my case and upholds my cause. He will bring me out into the light;I will see his righteousness. (Micah 7:9)
Isaiah 12:1
Then you will say on that day, "I will give thanks to You, O LORD; For although You were angry with me, Your anger is turned away, And You comfort me.
Hosea 6:1
"Come, let us return to the LORD. For He has torn us, but He will heal us; He has wounded us, but He will bandage us.
Isa.57:17 “Because of the iniquity of his unjust gain I was angry and struck him;
I hid My face and was angry, And he went on turning away, in the way of his heart.
18“I have seen his ways, but I will heal him;
I will lead him and restore comfort to him and to his mourners,
Mat 18:34 And his lord was wroth, and delivered him to the tormentors, till he should pay all that was due unto him.
It seems they will "come to Him" & "be ashamed" of themselves:
Isa.45:24 The people will declare, "The LORD is the source of all my righteousness and strength." And all who were angry with him will come to him and be ashamed.
And he that "comes to Him" shall find rest & He shall not cast out (Mt.11:28; Jn.6:37).
Isa.45:23 I have sworn by myself, the word is gone out of my mouth in righteousness, and shall not return, That unto me every knee shall bow, every tongue shall swear.
https://www.tentmaker.org/books/hope_beyond_hell.pdf