Job was perfect for his time, of course no man born of woman is ever totally without sin except for Jesus.
Seems ironic that the sons of God in Genesis 6 are considered as fallen angels, or demonic beings if you will, yet the timeline of Job really hasn't ever been established, so in reality the events portrayed in the Book of Job could be an reflection upon the days of referred unto in Genesis 6:2 or even Gen 11:5-7
5 And the LORD came down to see the city and the tower, which the children of men builded.6 And the LORD said, Behold, the people is one, and they have all one language; and this they begin to do: and now nothing will be restrained from them, which they have imagined to do.
7 Go to, let us go down, and there confound their language, that they may not understand one another's speech.
The overall moral of the story is, when everything we know about God is not making sense, just keep on believing in God because He will bring you through.
In fact the Book of Job tells of two accounts of the LORD bringing the sons of God
Now there was a day when the sons of God came to present themselves before the LORD, and Satan came also among them. Job 1:6
2:1 Again there was a day when the sons of God came to present themselves before the LORD, and Satan came also among them to present himself before the LORD.
Job 2:1
So if the sons of God presented themselves to the LORD then why did Satan come also among them, seems he was the only one begotten of the LORD thy God?
Jobs three friends actually made sense, God blesses those who are faithful to Him and bad things happen to those who reject God.
So if the LORD put Job in Satan's hand, (Job 2:6) And the LORD said unto Satan, Behold, he is in thine hand; but save his life, then where was Satan during that time if not with Job?
Now when
Job's three friends heard of all this evil that was come upon him, they came every one from his own place;
Eliphaz the Temanite, and
Bildad the Shuhite, and
Zophar the Naamathite: for they had made an appointment together to come to mourn with him and to comfort him.
Job 2:11
So if it was Eliphaz, Bildad and Zophar, then who is Elihu?
32:1 So
these three men ceased to answer Job, because he was righteous in his own eyes.
2 Then was kindled the wrath of
Elihu the son of Barachel the Buzite, of the kindred of Ram: against Job was his wrath kindled, because he justified himself rather than God.
3
Also against his three friends was his wrath kindled, because they had found no answer, and yet had condemned Job.
Job 32:1-3
It seems he just appeared like a thief in the night amongst them.