Now to get to your question about
Is everything bad from the enemy? How do we know if the enemy is working?
Is the enemy considered to be "satan" or "demons" or both at times?
Is cancer and sickness from the enemy?
I read these verses and made me wonder about how the enemy worked.
I will try to answer them.
Satans Goal is to overthrow God and become God... This is not possible because God is God, He is the "I AM".
Anyways, God is Love, Truth, Life... These actions, feelings, and characteristics that we know, are resemblances of God Himself. The word love does not describe Gods feelings but describes God himself (1 John 4:8) (1 John 4:16).
Since the words love, truth, holiness, etc. are God, than whatever is not of God is against God. (Matthew 12:30)
This means that Satan is not Love, Truth, Holiness, or Life... But he is Lies, Hate, Sin, and Death.
John 8:44
Ye are of your father the devil, and the lusts of your father ye will do. He was a murderer from the beginning, and abode not in the truth, because there is no truth in him. When he speaketh a lie, he speaketh of his own: for he is a liar, and the father of it.
So yes everything Bad is from Satan... He is the father of evil.
I would suggest that the enemy is Satan, the reasoning for this is because Satan is the father of evil.
As Christians we only do Good because of Christ, our redeemer. Since He payed for us in blood.
The enemy does evil because they belong to Satan and are in chains to him.
Ephesians 6:12 says 12 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.
So now, you can look at this in two ways. First, if America was at war with England. Some people would say "Obama is at war with Queen Elizabeth." And that would be correct. others might say "America is at war with England" and that would also be correct. In both cases the enemy (whether it be england or america) was shown. So the answer could be both in my opinion.
Cancer and Sickness are repercussions for our sin... It is a fallen world... Cancer and Sickness are because of our sin. And our ancestors sin... Romans 5:12-18
12 Wherefore, as by one man sin entered into the world, and death by sin; and so death passed upon all men, for that all have sinned:
13 (For until the law sin was in the world: but sin is not imputed when there is no law.
14 Nevertheless death reigned from Adam to Moses, even over them that had not sinned after the similitude of Adam's transgression, who is the figure of him that was to come.
15 But not as the offence, so also is the free gift. For if through the offence of one many be dead, much more the grace of God, and the gift by grace, which is by one man, Jesus Christ, hath abounded unto many.
16 And not as it was by one that sinned, so is the gift: for the judgment was by one to condemnation, but the free gift is of many offences unto justification.
17 For if by one man's offence death reigned by one; much more they which receive abundance of grace and of the gift of righteousness shall reign in life by one, Jesus Christ.)
18 Therefore as by the offence of one judgment came upon all men to condemnation; even so by the righteousness of one the free gift came upon all men unto justification of life.
Also Revelations 21:4 suggests that pain and suffering was not in Gods original design.. Since he is going to bring the creation back to it's Glory once He comes back since he holds the deed in his hand. Because he rose from the grave.
Now can satan cause pain and suffering and disease... Yes, you can see that in the book of Job he caused all of these things.
