Jesus has forgiven all sin. But the sin of unbelief in that fact condemns the unbeliever to hell.

Why is such a free and loving gift rejected by so many? ->They are rebellious by nature and they love sin.
And that attitude makes them enemies of good.

Those who allow evil to reign in their lives prefer the cover of darkness so they do not have to see the truth. They also prefer others to be in darkness so those do not see the wickedness either.