Job 2:4-7:

And Satan answered the LORD, and said, Skin for skin, yea, all that a man hath will he give for his life.
But put forth thine hand now, and touch his bone and his flesh, and he will curse thee to thy face.
And the LORD said unto Satan, Behold, he is in thine hand, but save his life.
So went Satan from the presence of the LORD, and smote Job with sore boils from the sole of his foot unto his crown.

Notes on Job 2:4-7:

Satan, not God, made Job sick.  There is no way to dispute this.  The only dispute people can have is the claim that “God allowed it,” which seems obvious from the context.  Why did God allow it?  And why could He not do the same in the New Testament?

These matters are explained in detail in the answer to the common objection to healing based on Job as well as the very long discussion Job Explained.  In short, you cannot be another Job because you have direct authority over Satan, who is the author of disease.  Job did not have this under his covenant, and Job was unaware that there was any being named Satan.  That is why Job blamed everything on God, and that is why God did not charge Job with sin for saying that God had done it.  Later, Job’s attitude deteriorated and he did make unfair accusations against God for which he had to repent.  Even Job said that if there had only been a mediator between him and God, he would not have stayed sick.  We do have a Mediator today (1 Timothy 2:5).  Even one of his foolish friends understood the concept of atonement bringing healing: “Deliver from going to the pit, for I have found an atonement...His flesh shall be like a child’s....”  These themes and many others are far more developed in Job Explained.

Job was sick for less than 1% of his life and God completely healed him and blessed him.  We would see many people similarly healed and blessed if preachers would harp on God’s healing of Job’s Satan-inflicted illnesses as much as they harp on Job’s sickness.  You are supposed to see the Lord’s mercy when you read about Job according to James 5:11.

See also:

Job Explained
Objection: Job Was a Godly Man, Yet God Let Him Get Sick
Condition: Bad Breath (Chronic)
Condition: Boils
Condition: Sores