Such verses seem to abrogate, obliterate, disregard, ignore, and/or go way beyond merely minimizing obligation to or even knowledge and awareness of moral Law, and - specifically - both the need to consistently and completely obey MORAL (not "ceremonial" livestock-slaughtering/dietary/temple-building) Law plus various degrees of anxiety or apprehension relating to incurring discomfort, inconvenience, and punishment for disobeying moral Law.
Sort of flies in the face of:
Matthew 7:22 On that day many will say to me: "Lord, Lord, did we not prophesy in your name, and exorcise demons in your name, and do many mighty works (even by "faith/trust/belief/whatever") in your name?"
Matthew 7:23 And then will I declare to them: "I never knew you; depart [away] from me, you evildoers."
James 2:14 What does it profit, my friends, if anyone says [they] have faith but have not works? Can [their] faith save [them]?
Discounting the awareness and knowledge of, the need for, and the obligation to always comply with moral Law automatically negates any realistic conception of what "sin" is, and what it actually is by God's definition in legitimate [correctly-translated] Scripture.
Relating to John 3:16 stated above, for example, why would the word "perish" come into mind whatsoever, pertaining to "believing in" (whatever that means) the Son who God gave, and how does that "belief in" relate (if at all) to obedience to or disobedience against moral Law?
Does God really "love the world?" The author John himself wrote:
John 15:18 If "the world" hates you, know that [they] have hated me before [they] hated you.
John 15:19 If you were of "the world," the world would love [their] own; but because you are not of "the world," but I chose you out of "the world," therefore "the world" hates you.
And what is "the world?"
Psalm 24:1 A Psalm of David. The Earth is the LORD's and the fullness thereof, the world and those who reside therein
Psalm 33:8 Let all the earth fear the LORD, let all the inhabitants of the world stand in awe [fear, or love?] of Him!
Psalm 49:1 . . . Give ear, all inhabitants of the world . . .
Psalm 50:12 If I were hungry, I would not tell you, because "the world" and all that is in "it" is mine.
Psalm 77:18 The crash of your thunder was in the whirlwind; your lightnings lit up the world; the Earth trembled and shook.
Psalm 89:11 The heavens are yours, the Earth also is yours (so that is why the Bible currently applies to us nowadays and we continue to be involuntarily obligated to respond positively to Earth-owner God and His Bible so we do not trespass on His property!); the world and all that is in it, you have founded them.
Psalm 90:2 Before the mountains were brought out, or ever you (not outer-space alien beings) had formed the Earth and the world, from everlasting to everlasting, you (not illegal aliens) are God.
Psalm 93:1 The LORD reigns; He is "robed" in majesty; the LORD is robed (latest fashion and style), He is dressed with strength. Yes, the world is established; "it" [they?] shall never be moved . . .
Psalm 96:10 Say among the nations: "The LORD reigns! Yes, "the world" is established, "it" shall never be moved; He will judge "the peoples" with equity."
Psalm 96:13 . . . He comes, He comes to judge "the Earth." He will judge "the world" with righteousness, and "the peoples" with His truth.
First John 2:15 Do not love "the world" or the things in the world. If any one loves the world, love for the Father is not in him.
A contradiction? Or, at least, a vital qualifier and balance?
As far as "belief" goes, "confidence in confidence alone" is quite insufficient for salvation.
As is human unreliable faith and polluted works.
James 2:19 You believe that God is one; you do well. Even the demons believe -- and shudder.
Belief and trust are two separate words, with two separate meanings, with trust going beyond mere belief, involving loving dependence upon and confidence in.
Psalm 9:10 And those who know your name put their trust in you, because you, LORD, have not rejected those who seek you.
Psalm 25:2 Oh my God, in you I trust, let me not be put to shame; let not my enemies celebrate over me.
Psalm 31:6 You hate those who pay regard to vain idols; but I trust in the LORD.
Psalm 31:14 But I trust in you, LORD; I say: "You are my God."
Psalm 33:21 Yes, our heart is glad in Him, because we trust in His holy name.
Psalm 37:3 Trust in the LORD, and do good; so you will reside and stay in the land, plus enjoy security.
Psalm 37:5 Commit your way to the LORD; trust in Him, and He will act.
Psalm 40:3 He put a new song in my mouth, a song of praise to our God. Many will see and fear, and put their trust in the LORD.
Psalm 40:4 Blessed is the person who makes the LORD their trust, who does not turn to the proud, to those who go astray after false gods!
The question then is: "Believe what?" relating to the Son that God gave. Believe that Jesus existed? Believe that that human who claimed "Before Abraham was, I AM" was God's Son? Believe that God gave His only Son? What does it means to "believe in" that Son? What's to believe about Him? That He was God's Son? That He was God's only Son? So what? What does believing that God gave His "only Son for the world" accomplish, and why would the result of that for those who do that "belief" be that they would not "perish" (whatever that means)?
What's to perish from? What is the potential or assured catastrophe in the future to not perish from? How does that relate to obedience now to the moral Law (if at all) given back then? What (if anything) has changed? Who (if anyone) has had the audacity to change it so that it no longer applies? How does that relate to "sin" by disobedience against the moral Law? How does that relate to "the fear of God?"
Won't everyone automatically be "saved?" Given a purgatorial second chance after death?
Romans 9:27 And Isaiah proclaims concerning Israel: "Though the number of the sons of Israel be as the sand of the sea, only a remnant of them will be saved."
Matthew 7:13 Enter by the narrow gate, because the gate is wide and the way is easy, that leads to destruction, and those who enter by it are many.
What type of "destruction" does inspired-Bible-author Matt have in mind? Is it complete annihilation into nothingness? Whoopie, if that!? (Where is adequate justice requiting gross injustice, then?) Or something else relating to frightening and horrifying mention of being forever suspended airless while tormented eternally with never-ending invisible flames?
Literal non-mythical/non-fairy-tale, non-allegorical/symbolic/metaphoric, hellfire and brimstone "for" (but actually against) the aberrant and arrogantly defiant?
If the Law is irrelevant, the abstraction of "sin" is also irrelevant and meaningless, and from that, the concept of "repentance" is also irrelevant and meaningless. If knowledge of and deliberate accommodation to moral Law is not required nor applicable nor mandatory, there is no need to fear nor worry about "sin" nor any need to "repent" (now or previously) concerning such an abstract concept.
No need to delete or not look/lust at porno images on or downloaded from the internet. No need for gals to have tied their loose long hair into an up-do or single back-of-head ponytail while being in general mixed-gender public view to avoid pseudo-innocently or flagrantly flaunting their sexually-alluring/obscenely-titillating immodestly-indecent mopheadedness of hair hanging below mouth level or slanting at an angle across their foreheads?
Numbers 5:18 [RSV, NASB] . . . and the priest shall set the woman before the LORD, and unbind the hair of the adulterously-suspect woman's head . . .
Song of Solomon 7:5 [RSV, NASB] Your head crowns you like Carmel, and your flowing locks (sexy mopheadedness), MY spouse/bride/wife/concubine (not "my" streetwalker/whore/slut/masseuse/escort/prostitute/mistress) are like purple; a king is held captive in the tresses.
First John 5:21 Little children, keep yourselves [away] from [immodest quasi-obscene sexually-oriented] idols.
Romans 10:3 Being ignorant of the righteousness that comes from God, and seeking to establish their own, they did not submit to God's righteousness.
Titus 1:16 They profess to know God, but they deny Him by their deeds; they are detestable, disobedient, unfit for any good work.
All throughout the Bible, in both Testaments, the "fear of God" phrase is used - over and over and over. What's to fear about God? Why was not the word: "respect" substituted for the word "fear?" Respect and Fear are two different words with obviously two different (but perhaps remotely related?) dictionary meanings.
"Respect" has to do with honoring though not necessarily loving nor trusting nor associating with, although certainly not being antagonistic nor hostile against someone equal or superior . . . whereas "fear" - of necessity, by dictionary definition - has to do with being AFRAID of though not necessarily hating nor mistrusting nor desiring segregation or isolation away from whoever is to be scared of.
And there is the enigma. Is it possible to be intensely afraid of someone who one simultaneously loves, trusts, and wants to draw near to and associate with?
How or why would one do that - that is, be very afraid of someone they not merely respect but want to be in close and closer companionship with?
And here we get back to First John 4:18 stated above. How can one engage in near-catatonic "fear of the LORD" while yet loving Him? How does "punishment" (for whatever cause?) fit into all this? "Punishment" for what, and when?
Which brings us back to the words: "repentance" and: "sin" and: "moral Law."
It can safely be stated that the moral Law of the Bible is perfect -- unlike questionable civil or government statutes, regulations, and related "law".
Consider our awareness and compliance with such civil and government statutes, regulations, and law, relating to the police (who are more that simply instructors or reminders of such law, but also physical enforcers of such).
Do you love the police? Do you hate the police? IF you love them, are you subtly or overtly or cautiously still substantially afraid of them, especially on the highways and freeways where they roam around in marked and non-marked squad cars ready to pounce on (i.e. punish with fines and more) those who even slightly disobey driving regulations and rules at any time?
Where I live, I see lawn signs stating: "We Support Our Police." It's a safe slogan, especially to the police who read those signs.
But the question remains, do those lawn sign proponents fear the police at the same time, realizing that violators against police-enforced law will be punished? How does that relate to First John 4:18 above as to perfect love for the police casting out fear of them as to the punishment they not might but instead will inflict on the lawless?
Is not God the Ultimate Cop when it comes right down to it?
Romans 2:8 . . . against (not "for") those who are factious and do not obey the truth, but obey wickedness, there will be wrath and fury.
You do all He says, and you will not get punished by Him. Both temporally and especially eternally. IF your "love" for Him results in you doing all He says, you will not get punished.
Matthew 5:19 Whoever then relaxes one of the least of these commandments and teaches "men" so, shall be called least in the kingdom of heaven; but he who does them and teaches them shall be called great in the kingdom of heaven.
NOTE: Many times English translations errantly state the word: "man" in the Bible for both genders, because when based upon the Greek root anthropos within inerrant Scrivener Trinitarian New-Testament Greek-Text Scripture from which we get our word "anthropology" (which is the scientific study of humanity of both genders, not merely male humans), obviously both genders are referred to.
Romans 7:22 I delight in the [moral] Law of God, in my inmost self . . . (why did not Paul instead say: "I delight in the gospel of Christ's atonement for me"? or: "I delight in my unreliable trust or frequently-faulty faith in God often doubting that He will (not can, of course) provide for me adequately and on time, not my own righteous instead of wicked works of, not against, the moral Law"? ).
Why did Paul not say that we are "justified" by faith, not by doing wicked works against the Law? Why did he not qualify what type of works (whether good or evil) we are not justified by? Why did he apparently talk down doing good works for, instead of against, the moral Law?
IF we are not justified by doing lawful works, then the opposite (by default) is (logically, and of necessity) true: We are justified by doing unlawful works. Even by faith in whatever we have faith in. Dependable tools of the trade we rely upon.
Matthew 7:16 You will know them by their works (i.e. fruits). Are grapes gathered from thorns, or figs from thistles?
Matthew 7:20 Thus you will know them by their works (that is, "fruits").
Luke 6:46 "Why do you call me 'Lord, Lord,' and not do what I tell you?"
Romans 2:13 It is not the hearers of the Law who are righteous before God, but the doers of the Law who will be justified. [Naturally, one has to first hear to then do].
First Timothy 4:16 Take heed to yourself and to your teaching; hold to that, for by so doing you will save both yourself and your hearers.
Titus 1:16 They profess to know God, but they deny Him by their [good, or instead evil?] deeds; they are detestable, disobedient, unfit for any good work (or "deed").
Hebrews 4:2 Good news came to us just as to them; but the message which they heard did not benefit them, because it did not meet with faith in the hearers. [One first has to believe that Law obedience is necessary, for them to consequentially then actually obey that Law]
James 1:22 But be doers of the word, and not hearers only, deceiving yourselves.
But again, all that relates to the previous words: "repentance" and "forgive us our sins" and "moral Law" (violation against which Law necessitates the initial and ongoing forgiveness and repentance).
Hebrews 10:26 If we deliberately sin after receiving the knowledge of the truth (of which Law is a vital part), there no longer remains a sacrifice for sins (not simply our own, but especially Christ's atoning death on the cross which had and would have continued to apply to us),
Hebrews 10: 27 but a fearful prospect of judgment, and a fury of fire [Fire] which will consume the adversaries.
Second Thessalonians 1:9 They shall suffer the punishment of eternal destruction and exclusion [away] from the presence of the Lord and from the glory of His might.
Luke 16:23 . . . and in Hades, being in torment, he lifted up his eyes, and saw Abraham far off and Lazarus in his bosom.
Luke 16:28 . . . "I have five brothers . . .warn them, lest they also come into this place of torment."
Revelation 14:11 And the smoke of their torment goes up to the ages of the ages; and they have no rest, [24/7] these worshipers of the beast and his image, and whoever receives the  mark [tattoo] of his name."