Epistemic status: provisional.
31 May 2021: see this addendum.
Gating Off Voices
Not every voice is worth listening to.  Sometimes there are voices
that tell you you are worthless, a failure, or doomed, or ones that
tell you that this life is all that matters, or ones which are other
people's misinterpretations of you, or their agendas for you -- there
are probably other unworthy voices that are out there.
So it can seem appealing to shut those voices out, to irrevocably
invalidate them, so that you can get on with your life.
But what if you're wrong about which voices are unworthy, and one
which you shut out might be the voice of God?  There is some danger
of hardening here.
The state of mind where you put up no resistance to the voices
that try to colonize your mind is one in which it is difficult or even 
impossible to follow God with your whole being.  Perhaps your real 
disposition, underneath all the colonizations, is one of following God 
with your whole being, if that state of non-resistance to colonization is 
something you can't help.  But if you can help it, it isn't clear to 
me that preferring non-resistance (such that you don't try rejecting
any voices) is a better way to avoid hardening, since that preference 
roots you in a stable and seemingly undefeatable belief or believing 
regime, the one in which you can never commit.  "I can never commit to 
God" may be just as hardened as "I reject God".
In that case, you always take a risk of being hardened, so, 
fearing and respecting the fact of that risk to the appropriate degree, 
you might as well choose the path that helps you serve God best as you 
understand him right now, in hopes that he will keep working with you 
so that someday your understanding presents no obstacle to loving and
trusting him.  If God doesn't exist, then hardening doesn't matter, 
so if hardening matters, it matters how we relate to God, and 
sometimes it is best to deliberately shut out some of the 
pathological voices
in order to hear his better.  God can see you trying to hear him,
and knows your true disposition, and wants you to succeed in 
hearing him.
A mind that shuts out voices is in danger of becoming intolerant
and totalizing.  It's important that whatever you do psychologically,
whether in the realm of perception, emotion, willing, or intellectual 
believing, you do it as though God exists.  Among other things,
God is one who wants you and everyone else to be saved, who is the 
father of you and everyone else, and whom you and everyone else can 
trust.  With God's Spirit, we don't
see things through the lens of control and self-preservation.  We 
can believe firmly without mistreating or enslaving people.
Reality must be that which we can think about?
Does all this give a rationale for refusing to listen to voices
that say something like "You have a tiny but 
non-Pascalian chance of going to a hell
of eternal conscious torment"?  The thought that you could go to hell 
might cause you to love and trust in God more.  Certainly that's how 
it seems to have worked as a part of evangelism in the past.  Probably 
it is not necessary to believe in eternal conscious torment (ECT) for 
that purpose.  (Annihilation is sufficiently motivating, and sometimes 
even that is not necessary to motivate people.)  But ECT got people to 
take God seriously, which is part of loving and trusting him.
  
On the other hand, the thought of hell, or of ECT specifically, 
can easily not have that effect.  So it's fine to ignore it if it
takes you away from God.
(I don't believe that MSLN gives reason to believe
in ECT and from what I've read from other people as of today (25 May
2021), I'm fairly confident that neither does the Bible, although
I should address that question in more detail at some point.)
I think we might have the effective attitude of "whatever
our belief structure, we know that ECT doesn't exist".  The thought
of ECT is so horrible that if we took its possibility seriously,
we would go crazy, and going crazy is a priori not an option
for thinkers.  Well-being trumps truth -- but we could even claim
that truth actually always contains well-being.  (Maybe this claim
makes sense from this 
perspective -- to think, feel, and intuit in one whole means 
that the knowing itself is healed of its fragmentation, and healed
knowing perhaps inherently creates and requires healthy knowers.)  
As an epistemological principle, we could claim that what actually is 
is always in line with truth, and thus not have to deal with ECT.  
Something like this seems to be what people may already believe 
implicitly, at least with respect to ECT.
It does seem odd to say that things which are too horrible to think
about productively can't actually happen.  We see horrible things happen,
but maybe they're not horrible enough?  Is there some point at which, as 
things become more horrible to imagine, they cross a line and become 
impossible?
So it's not that the inherent horribleness of ECT makes it impossible,
it's that when we know that it is impossible, we implicitly know that
something else is true which for some reason allows horribleness to happen,
but not ECT.
What kind of metaphysical reason could back that up?
Certainly the God of MSLN could.  Materialism could, 
as well.  Probably other beings or realities could.  Whatever it is, it 
has to be able and willing to (or "disposed to", in the case of impersonal 
reasons) exclude possibilities, and specifically exclude ECT.  We might 
think that we know for certain that ECT-affirming Christianity and Islam 
aren't true, but that annihilation-affirming versions of them could be 
true.
The Proportionality of Truth
Another approach could be to say that belief in ECT causes us to
disregard the proportionality of truth.  Truth is always a thing which
has its relationships.  If we really took the possibility of ECT 
seriously, if it has a vanishingly small likelihood, then if it 
dominates all the rest of our thinking, we no longer see anything else.
But that "anything else" is far more likely than the likelihood of
ECT.  So to know the truth, we have to take into account all the 
good of all the "anything else"'s, and those possible goods should
not be ignored.
I think MSLN is likely -- I'm sure my credence
will vary over time, but let's say today it is 90%.  In 90% of possible
futures, as long as I remain true to God, I will experience infinite
(or, more accurately, everlasting) positive utility.  What do I think
my credence is of non-MSLN outcomes?  As I see things now, there's
a tight, perhaps 1 to 1 connection between the idea that reality only
consists of consciousness, and MSLN.  So what is my sense that there
could be reality in addition to consciousness?  Maybe 10%.  Within
that 10%, how much room is there for ECT?  I don't really know, but
I can try to guess, based on reasons why ECT might exist.
  
Maybe some kind of God or god-like being might ordain it (like
the Stringent Invisible Flying 
Spaghetti Monster).  He would use it to motivate people to care 
about things.  Maybe a human society would.  But one could also 
imagine a sadistic god.
Would humans want to torture other humans everlastingly?  Maybe a 
few would, but what are the odds that they would take over the future, and 
be able to resurrect you to be part of their sadistic world?  We have 
to imagine a world where people would even bother to remember whatever 
made you up, in order to faithfully reproduce you (to the extent that's 
possible) and then torture you (or that copy of you?).  Are people 
(personal beings) really that sadistic?  Or would they get bored of 
that instead?  Dystopian futures are certainly possible, but are they 
likely, and likely to affect you, and will they actually attain ECT?  
"Eternal" is a long time, and hard to guarantee, unless you have 
something like complete sovereignty over reality.
So something smaller than 10% allows for ECT, perhaps something
very small, perhaps as high as 1%.  (These numbers are made up,
but reflect my subjective sense today.)  I feel like 1% is as high
as I would go, as an extremely safe assumption that would definitely
exceed the real probability, so as to have a "safe" estimate of the
risk.
  
One remaining filter is, if ECT exists,
will I ever be subject to it?  Or, in other words, what percentage of
existing beings will ever be subject to it?  This filter reduces the
likelihood further.  If ECT is meant as a punishment, then what if
most beings simply adjust and stop meriting the punishment?  If ECT
is meant as sadism, how much do sadistic personal beings update their
sadistic satisfaction to match large quantities of people tortured?  
Or are 1,000 tortured as gratifying as 1,000,000, so they don't bother
with more than 1,000?  To the extent that sadism is basically just a 
form of hedonism, why don't sadistic hedonists wirehead, or put themselves 
in experience machines?  They could get away with that much more easily
than actually torturing people, in the likely case that sadism is not 
popular.
Maybe some altruists who are not hedonists would be willing to torture 
people for all time for the tortured people's own good?  To bring justice
to someone is to take them seriously as a moral agent.  These altruists 
would have to be unaware of the likelihood that MSLN is true.  (As would 
any of these hypothetical people who might cause ECT.)  To torture people 
who don't really deserve it seems like a risky thing to do, given that 
there might be a God who has to suffer whatever suffering you cause those 
you are punishing, who alone has the right to judge and punish people, 
knowing as he does the actual truth of who deserves punishment.  If you 
exact torture with enough gusto or commitment, maybe you have 
hardened, since torture is not something that 
God inherently likes.
  
Is it likely that altruism will evolve into something that seeks to 
exact eternal conscious torment in the secular timeline?  That sounds 
somewhat far-fetched, especially given the possibility of thinking of MSLN.  
But there is some possibility of it.  Maybe a particularly worldly-minded 
religious movement could do it.  But for every worldly-minded religious 
movement that might do it, there would be others that wouldn't.
To return to the subject of gods:  Could a god (a superpowerful being)
know that MSLN wasn't true?  God can know that MSLN is true (if it is),
simply by knowing that everything exists, fundamentally, by his will
(evil follows from the wills of beings other than him, whose freedom he 
wills).  But other superpowerful beings, no matter how much they could 
find out, would probably be vulnerable to doubts that the God of MSLN 
might exist.  This would lower such a god's confidence that it could 
torture us with impunity.
I think, again trying to make an extremely safe 
assumption, that at most 1% of all beings in an ECT-affected reality 
actually experience ECT.  This assumes that ECT-infliction is not done
throughout history, it is (exceedingly?) unlikely that anyone could 
bring back past people to be tortured in a future present, and when 
ECT-infliction is done, it generally doesn't affect the whole 
population, and the likelihood of it happening at all is somewhat low.
So if there's a 90% chance that as long as I am true to God (something
which shouldn't be impossible as long as I keep caring about it) I will
experience an everlastingly good outcome, and there is a 0.01% (1% of 1%)
chance, at most, that I will experience ECT, then the approach of
truth is to say I must take the 90% chance of good life forever as 
a substantial plenitude of potential well-being, which is overwhelmingly
real to me, sustaining and building-up to think about, and the 0.01%
chance of ECT, while real, does nothing to diminish the 90% of good
that is promised.  If the 90% can't diminish the 0.01%, the 0.01% 
can't diminish the 90%.
(Does this mean that God can bear what we consider unbearable 
forever if he has enough counterweighing good experience?  And thus 
he could bear the pain of ECT for all eternity without relieving it?
Here's a reason why not.)
If you can see things that way, I think thoughts of ECT aren't 
overwhelming. This is proceeding according to an epistemology of 
this kind of truth, 
of seeing what is dark but also seeing what is light, and seeing it
as a whole.  This can be contrasted with a kind of 
survival epistemology, which sees
the avoidance of death and suffering as the criterion when processing
reality (instead of looking at reality as a whole for its own sake),
which thus focuses (or hyper-focuses) on threat.
This approach does not shut out voices, but adds them, still to
accomplish a similar goal.
This may be the answer to the 
question "Does ECT dominate reason?".  ECT does not dominate reason,
because as long as we have a significantly more likely "eternal conscious
rest" to contrast with it, we will take ECR more seriously than ECT,
proportional to ECR's likelihood, no longer "mugged" by threat.
Bad voices close you off to reality
At the beginning of this post, I mentioned voices that say "you are 
worthless, a failure, or doomed, or ones that tell you that this life 
is all that matters, or ones which are other people's misinterpretations 
of you, or their agendas for you".  What's interesting about all these
voices is that they close off access to other voices.  If you're worthless,
then you no longer access God's voice, the God who feels your pain and
puts up with your sin -- real costs to him indicating real value.  Likewise,
how can you know that you are a failure, or doomed?  Only if you 
close off your mind to possibilities, including the possibility (the 
likelihood) of God.  When people misinterpret you, they tend to want to 
limit you, and when they have agendas for you, they want to commit you to 
some kind of commitment.  All of these things try to get you to see just
one part of reality.