....why do you think God would allow satan to do this....
To Show Us First Liar
Then Satan answered the LORD, and said, Doth Job fear God for nought?
Hast not thou made an hedge about him, and about his house, and about all that he hath on every side? thou hast blessed the work of his hands, and his substance is increased in the land.
But put forth thine hand now, and touch all that he hath, and he will curse thee to thy face. Job 1:9-11
Eating His Dust Dinner
Then Job arose, and rent his mantle, and shaved his head, and fell down upon the ground, and worshipped,
And said, Naked came I out of my mother's womb, and naked shall I return thither: the LORD gave, and the LORD hath taken away; blessed be the name of the LORD.
In all this Job sinned not, nor charged God foolishly. Job 1:20-22
Or Was It To Show Us
And it was so, when the days of their feasting were gone about, that Job sent and sanctified them, and rose up early in the morning, and offered burnt offerings according to the number of them all: for Job said, It may be that my sons have sinned, and cursed God in their hearts. Thus did Job continually. Job 1:5
God's Power And Grace
And the LORD turned the captivity of Job, when he prayed for his friends: also the LORD gave Job twice as much as he had before. Job 42:10
....why do.... Christian(s).... murmured against God....
Wilt thou also disannul my judgment? wilt thou condemn me, that thou mayest be righteous? Job 40:8
I have heard of thee by the hearing of the ear: but now mine eye seeth thee.
Wherefore I abhor myself, and repent in dust and ashes. Job 42:5-6
....And the final question why do you think God....
For I know that my redeemer liveth, and that he shall stand at the latter day upon the earth:
And though after my skin worms destroy this body, yet in my flesh shall I see God:
Whom I shall see for myself, and mine eyes shall behold, and not another; though my reins be consumed within me. Job 19:25-27