This is a question about what tests hermeneutics uses to distinguish quotes-from-canon from canon.
It isn't about how to interpret Psalm 5:5. But there is a brief follow-up question about Psalm 91, which I'll put at the bottom.
I'll find it easiest to present an escalating series of problems, to show what I'm on about, and if it's a case of "go read these" that's of huge help
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WHAT REAL TESTS ARE USED FOR THE BELOW?
TEST 1
A translation of Psalm 5:5 is recited aloud to two blindfolded exegetes from the same system.
The boastful shall not stand before your eyes; you hate all evildoers. || The boastful shall not stand before your eyes; you hate all evildoers.
I assume they would both test if it's canonical by comparing it with a known-good authoritative version. And that they'll agree it's a translation of scripture.
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TEST 2
Psalm 5:5 is played again with the blindfolds removed, they see:-
A student reading aloud from a book || A televisual confrontation between two fictional cyborgs
Well I assume an issue arises here, but they have to use the same test. I suppose: what context does the canonical verse appear in?
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TEST 3
The replies are:-
"This is a philosophy book by our ruler, but we hid Psalm 5:5 in the dustcover" || "Movies like this are how the missionaries taught us to share God's word in a disapproving society"
That might reach a conclusion that neither is canonical, but I suppose exegetes can consider it their duty to measure the extent or provide a granular report
So perhaps as a follow-up: what are the characteristics and values of this other work Psalm 5:5 has been hidden in?
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TEST 4
"Our ruler is a despot and his book explains how to boast and do evil" || "The movie's story is a translation of David & Goliath (1 Samuel 17). The imagery is from illustrated versions of John Bunyan."
Test 4 might only confirm the enquiry left the domain of exegesis at Test 3. Or depending on the exegetes' conception of their outward-facing/societal role, they might find a further notable/in-scope difference because:- the version hidden in the book can't be confused with its context, whereas the movie version has altered Psalm 5:5's meaning by resituating it into 1 Samuel 17
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TEST 5
The makers of the movie decide they don't want to alter Psalm 5:5's meaning, so they replace that part of the dialogue with a proposed converse: "I will not remain seated in the presence of the boastful". They ask if this sentiment is present in Psalm 91 (You Are My Refuge and My Fortress), particularly at Psalm 91:10 where the speaker has moved from being defended by God to fighting for God.
The exegetes can report whether Psalm 91 dovetails with Psalm 5. They could say (all things being equal) helping the movie is a positive social outcome of their exegesis, or that the previous four tests risk Eisegesis - but this isn't capable of being answered in abstract.
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ABOUT PSALM 91
Psalm 91:1 - He who dwells in the shelter of the Most High will abide in the shadow of the Almighty.
Psalm 91:2 - I will say to the LORD, “My refuge and my fortress, my God, in whom I trust.”
Psalm 91:10 - no evil will befall you, no plague will approach your tent.
Is there here a marked progression from God's shelter (cether) construed as his sacred dwelling-place, to a fortress (matsuwd) where the Psalmist wants to hide, to a battlefield tent (ohel) ?
From Strongs, the first two I think are straightforward. ohel was used of the tabernacle, mainly of domestic tents but also military camps e.g. Judges 7:8, 1 Samuel 4:10 https://biblehub.com/hebrew/strongs_168.htm
As a sanity-check, Psalm 91 has a probable composition date of 1015 (https://www.blueletterbible.org/study/parallel/paral18.cfm) and the book of Judges was c. 1125 b.c. (https://www.biblegateway.com/resources/encyclopedia-of-the-bible/Book-Judges).
If there is a marked progression, I suppose it might have the Psalmist turning their heart around from seeking the Lord's help to serving the Lord and understanding that in truth shelter is found in the fearless service of God.
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