Can’t understand God’s Anger?
Simple: It’s for your “own” good – correction – even in hell (if the need be) so that one day, you too may be “restored to life” according to His Will for you!

“The anger of the LORD will not turn back until He fully accomplishes the purposes of His Heart. In days to come you will understand it clearly.” (Jeremiah 23:20)

Remember, He has only One Ruling Purpose, which is “to Save the World” (John 3:17)

It’s ok. Some are “slow learners” (are only able to understand it ‘later’ during the ‘latter days’):

“The fierce anger of the LORD will not turn back Until He has performed and until He has accomplished The intent of His heart; In the latter days you will understand this.” (Jeremiah 30:24)

P/S:

Rebuttal: Before some eternal hell believing crusader or zealot “tries” to falsely accuse me of twisting Scripture (because his idea of “all anger” or “fierce anger” of God must yield the “result” of “eternal hell/eternal torture” on the inflicted and has ‘nothing’ to do with the purpose of ‘saving the world’ as mentioned in John 3:17 above), here’s the ‘literal’ Biblical answer:

“Therefore, wait for Me (LORD) — an affirmation of Jehovah (LORD), For the day of My rising for prey, For My Judgment [is] to gather nations, To assemble kingdoms, To pour out on them Mine Indignation, All the heat of Mine Anger, For by the Fire of My jealousy consumed is all the earth.

For then do I turn unto peoples a pure lip, To call all of them by the Name of Jehovah, To serve Him [with] one shoulder.” (Zephaniah 3:8 – 9)

It doesn’t get any more “clearer” or “literal” than the verse above:
Note that in the last verses aforementioned, God is pouring out “All His Anger” (not ‘some’) in “Indignation” (fierceness) for being “Jealous” (because He doesn’t want you to go astray anymore – He doesn’t rejoice in you ‘burning’ or being ‘lost’ in darkness – His Jealousy is ‘Positive’ aimed at bringing you back!)

What is the “result” or “outcome” for “All” the Fierce Anger of God?
Eternal hell or sadistic torture with “no rehabilitation”? No!

Quite the “opposite”, namely: The verses (literally) state that upon whom the Full Fierce Anger of God has been inflicted, these “resulted” in having a “pure lip” and even “serving Him” in “One” shoulder (All Saved in the “end” – fully rehabilitated).

This agrees with the rest of New Testament Scriptures which Speak about The Mystery of Christ to “gather in One all things in Christ” (Ephesians 1:10), “to fully Reconcile all things to Himself” (Colossians 1:20), to fulfill the “Restoration of All things” which was spoken by all His Holy Prophets (Acts 3:21) being Truly the “Saviour of the World” (1 John 4:14)

How come the “other Christians” couldn’t understand all these things “literally” (even plainly)? It must be analogous to the case of Moses versus Miriam (the prophetess/worship leader/tambourine dancer) & Aaron (high priest/the no.1 pastor ordained by God too) as it was in Numbers 12 (on a different issue):

“He (The LORD) said, “Listen to My Words:

“When there is a prophet among you,
I, the Lord, reveal myself to them in visions,
I speak to them in dreams.
But this is not true of my servant Moses;
he is faithful in all my house.
With him I speak face to face,
clearly and not in riddles;
he sees the form of the Lord.
Why then were you not afraid
to speak against my servant Moses?”
(Numbers 12: 6 – 8)

You see folks, it’s Christian versus Christian again:

Moses (the Christian with whom God spoke “literally” or “plainly”)

Miriam and Aaron (the Christians with whom God only spoke in “visions & dreams” as well as in “riddles” – probably that’s why many of our Miriam-like-sisters and Aaron-like-brothers in Christendom see everything in “idioms”)

Which type of Christian are you?
God obviously Speaks “literally” to only the Moses-Type-True-Christians.

Let Scripture interpret Scripture