1) It originated in heaven with a perfect, created angel called Lucifer. (Ezekiel 28:12-15; Isaiah 14:12)
2) God is in no wise responsible for the entrance of sin. It is an intruder and there is no reason for its presence. God IS LOVE, is written all over the Bible.
3) Every created being is given free choice. (starting with all created beings in heaven itself and now here on earth, "Choose ye this day....")
4) Evil existed before this world, and everything in it, was created, although they were created perfect. God's creation was "very good" - Genesis 1:31. (In the garden of Eden was put the tree of the knowledge of good and evil - there was no evil before Lucifer, thus in the garden he was already Satan).
5) Lucifer came to be called Satan, the devil, after his fall; and since he impersonated a snake in the garden, he is also known as that serpent; as well as the dragon. (So when you see reference to the dragon in the Bible, you can know it is Satan - see Revelation 12:9 and Rev. 20:2)
Many caricature the devil, with his little red arrow-tail, horns, pitchfork and impish body and face.
Our best bet is to resist the devil, flee to God and let God fight our battles with him. Find out, through reading God's word, what is the will of God and who, exactly we're fighting against. We need to know our foe. We can't trivialize Satan, and "play with fire". He is a force to be reckoned with. Don't take him lightly. Figure out where he wants to deceive you so you will be able, with God's help, to discern evil and turn from it.
And above all, don't forget that God has overcome Satan on our behalf. Trust in the one who can save you. God has provided us with armour:
Eph 6:12 - 17
"For we wrestle not against flesh and blood, but against principalities, against powers, against the rulers of the darkness of this world, against spiritual wickedness in high places.
Wherefore take unto you the whole armour of God,
that ye may be able to withstand in the the evil day, and having done all, to stand.
Stand therefore, having your loins girt about with truth,
and having on the breastplate of righteousness;
and your feet shod with the preparation of the gospel of peace;
Above all, taking the shield of faith,
wherewith ye shall be able to quench all the fiery darts of the wicked.
And take the helmet of salvation,
and the sword of the Spirit, which is the word of God....."
More about what Satan is up to in a later blog. I don't want anyone to be surprised - and you may already be aware of all this - it won't harm to review it - but just in case - this knowledge might save you from falling into Satan's deceptions!