The word scapegoat literally comes from the Jewish tradition of Yom Kippur in which some ritual was performed and two goats would be taken. One sacrificed to YHWH and the other sent into the wilderness and pushed off a cliff for azazel (satan) which atoned for the sins of israel.

Once Jesus Christ came and died on the the cross he became the new scapegoat, so to speak - the sins of man are placed on Him.

Also I'm not sure why satan is associated with the goat, but it might have something to do with the goat being a father selfish and stubborn animal.

Hence the name scapegoat and the association of a goat with satan.

How to fight and invisible enemy that you think does not exist?

"Then was Jesus led up of the Spirit into the wilderness to be tempted of the devil.

And when he had fasted forty days and forty nights, he was afterward an hungred.

And when the tempter came to him, he said, If thou be the Son of God, command that these stones be made bread.

But he answered and said, It is written, Man shall not live by bread alone, but by every word that proceedeth out of the mouth of God.

Then the devil taketh him up into the holy city, and setteth him on a pinnacle of the temple,

And saith unto him, If thou be the Son of God, cast thyself down: for it is written, He shall give his angels charge concerning thee: and in their hands they shall bear thee up, lest at any time thou dash thy foot against a stone.

Jesus said unto him, It is written again, Thou shalt not tempt the Lord thy God.

Again, the devil taketh him up into an exceeding high mountain, and sheweth him all the kingdoms of the world, and the glory of them;

And saith unto him, All these things will I give thee, if thou wilt fall down and worship me.

Then saith Jesus unto him, Get thee hence, Satan: for it is written, Thou shalt worship the Lord thy God, and him only shalt thou serve.

Then the devil leaveth him, and, behold, angels came and ministered unto him."

Matthew 4 1-11

"And when he was come to the other side into the country of the Gergesenes, there met him two possessed with devils, coming out of the tombs, exceeding fierce, so that no man might pass by that way.

And, behold, they cried out, saying, What have we to do with thee, Jesus, thou Son of God? art thou come hither to torment us before the time?

And there was a good way off from them an herd of many swine feeding.

So the devils besought him, saying, If thou cast us out, suffer us to go away into the herd of swine.

And he said unto them, Go. And when they were come out, they went into the herd of swine: and, behold, the whole herd of swine ran violently down a steep place into the sea, and perished in the waters.

And they that kept them fled, and went their ways into the city, and told every thing, and what was befallen to the possessed of the devils.

And, behold, the whole city came out to meet Jesus: and when they saw him, they besought him that he would depart out of their coasts."

Matthew 8:28-34

I don't believe in a god/devil nor do i believe in terms like "evil" infact what does evil even mean? are you suggesting people are born morally corrupt? that's ridiculous.

I think everybody knows what evil is - it's the opposition to good.

For example sadistically beating somebody up for no other reason than to feel good about your self is evil

Torturing animals for no reason is evil - in fact plenty of serial killers start off by torturing animals in their youth and graduate to torturing and murdering humans.

In fact you might say that being a serial killer is in fact evil - it is done with the sole intent to be selfish and inflict pain onto another living creature.

Eh, wrong.

I'm sure we can both agree the examples you gave are "morally wrong" or "bad acts" but the term "EVIL" doesn't add anything more than saying it's bad or wrong, instead it suggests a more spiritual force at hand.

Well sure, you can ignore the point I made and ignore the fact that the world 'evil' is in every known english dictionary and play the game of semantics all you want to feed your prideful ego.

False
And that is not the origin of the term "scape goat"

Misc needs to know, when you intended to penetrate your innate, did you say no homo?

The most clever of the tricks of the Devil is to persuade you that he does not exist! - Charles Baudelair

Satan has more wisdom than any man to ever walk the earth and he puts it to practise.

How can you fight against an invisible enemy who you're told doesn't exist?

It's the same deal as criminals who put somebody else as the figure of authority whilst they pull the strings.

The ONLY way for a human to fight satan is with the help of Jesus Christ.