Sin is a violation of God's law

Everyone who sins breaks the law; in fact, sin is lawlessness. 1 Jn 3:4

All wrongdoing is sin, 1 Jn 5:17

Indeed I would not have known what sin was except through the law. Rom 7:7

Sin is what makes true peace impossible for unbelievers

But the wicked are like the tossing sea,
which cannot rest,
whose waves cast up mire and mud.
"There is no peace," says my God, "for the wicked." Isa 57: 20-21

Woe to those who plan iniquity,
to those who plot evil on their beds! Micah 2: 1

All have sinned

for all have sinned and fall short of the glory of God, Rom 3:23

"There is no one righteous, not even one;
there is no one who understands,
no one who seeks God.
All have turned away,
they have together become worthless;
there is no one who does good,
not even one." Rom 3:10 - 12

Sin makes the sinner worthy of death

For every living soul belongs to Me, the father as well as the son--both alike belong to Me. The soul who sins is the one who will die. Ezk 18:4

Then, after desire has conceived, it gives birth to sin; and sin, when it is full-grown, gives birth to death. James 1:15

For the wages of sin is death, but the gift of God is eternal life in Christ Jesus our Lord. Rom 6:23

Sinners can do nothing to earn salvation

All of us have become like one who is unclean,
and all our righteous acts are like filthy rags;
we all shrivel up like a leaf,
and like the wind our sins sweep us away. Isa 64:6

For the wages of sin is death, but the gift of God is eternal life in Christ Jesus our Lord. Rom 3:20

A man is not justified by observing the law, but by faith in Jesus Christ. So we, too, have put our faith in Christ Jesus that we may be justified by faith in Christ and not by observing the law, because by observing the law no one will be justified. Gal 2:16

Sinners cannot change their own sin nature

Although you wash yourself with soda
and use an abundance of soap,
the stain of your guilt is still before Me,"
declares the Sovereign LORD. Jer 2:22

Can the Ethiopian change his skin
or the leopard its spots?
Neither can you do good
who are accustomed to doing evil. Jer 13:23

the sinful mind is hostile to God. It does not submit to God's law, nor can it do so. Those controlled by the sinful nature cannot please God. Rom 8: 7 -8

Sinners are therefore in a helpless state.

Just as man is destined to die once, and after that to face judgment, Heb 9: 27

There is nothing concealed that will not be disclosed, or hidden that will not be made known. What you have said in the dark will be heard in the daylight, and what you have whispered in the ear in the inner rooms will be proclaimed from the roofs. Lk 12: 2 -3

This will take place on the day when God will judge men's secrets through Jesus Christ, as my gospel declares. Rom 2:16

But the cowardly, the unbelieving, the vile, the murderers, the sexually immoral, those who practice magic arts, the idolaters and all liars--their place will be in the fiery lake of burning sulfur. This is the second death." Rev 21: 8

Of God and men
Of God's holiness
Of men's sin
Of Jesus Christ and what He did
Of God's call to sinners
Of counting the cost first
Of trusting in Jesus