Is it possible that the words used in the 4 gospels belong to people expressing their own emotions sometimes very cruel ?

No

2 Timothy 3:16 KJV — All scripture is given by inspiration of God, and is profitable for doctrine, for reproof, for correction, for instruction in righteousness:

You demons are obvious 

People are stubborn and divine judgment is a certainty. Make of that what you will.

Yes ......

on to the next Quacking Duck 

or put it on Donald's bill 

There is no proof that Jesus was accurately quoted word for word, by the authors of the Gospels.  But the gist of the points that were made probably are accurate.

NO.........

on to the next question.

Those words express justice.

Jesus had to die to save us.

He paid for us. That's justice. 

Romans 6:23

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

Isaiah 53:5

But he was wounded for our transgressions, he was bruised for our iniquities: the chastisement of our peace was upon him; and with his stripes we are healed.

Hell is not just a word, it's real.

It is a good point . Those words are not used only by jesus' disciples who wrote the bible. It-is true Jesus was doing Good  as well he was telling the truth for what will happen to people if they dont turn away from their sins. And this is not only about jesus disciples even all prophets in the old testament said these kind of words to make people turn away from their sins and those prophets was saying what God told them to say