Job 1:6-12 NIV
6One day the angelsa came to present themselves before the Lord, and Satanb also came with them. 7The Lord said to Satan, “Where have you come from?”
Satan answered the Lord, “From roaming throughout the earth, going back and forth on it.”
8Then the Lord said to Satan, “Have you considered my servant Job? There is no one on earth like him; he is blameless and upright, a man who fears God and shuns evil.”
9“Does Job fear God for nothing?” Satan replied. 10“Have you not put a hedge around him and his household and everything he has? You have blessed the work of his hands, so that his flocks and herds are spread throughout the land. 11But now stretch out your hand and strike everything he has, and he will surely curse you to your face.”
12The Lord said to Satan, “Very well, then, everything he has is in your power, but on the man himself do not lay a finger.”
Then Satan went out from the presence of the Lord.
What is Satan, Devil?
And Satan came also - This word also is emphatic in the original, השטן hassatan, the Satan, or the adversary; translated by the Septuagint ὁ Διαβολος. The original word is preserved by the Chaldee, Syriac, and Arabic; indeed, in each of them the word signifies an adversary.
1 Peter 5:8, plainly refers to this place; and fully proves that השטן hassatan, which he literally translates ὁ αντιδικος, the Adversary, is no other than ὁ Διαβολος, the Devil, or chief of bad demons, which he adds to others by way of explanation. There are many διαμονες, demons, mentioned in Scripture, but the word Satan or devil is never found in the originals of the Old and New Testaments in the plural number. Hence we reasonably infer, that all evil spirits are under the government of one chief, the Devil, who is more powerful and more wicked than the rest.
From the Greek Διαβολος comes the Latin Diabolus, the Spanish Diablo, the French Diable, the Italian Diavolo, the German Teuffel, the Dutch Duivel, the Anglo-Saxon and the English Devil, which some would derive from the compound The - Evil; ὁ πονηρος, the evil one, or wicked one.
However, it should be observed, that Satan, no less than the other celestial spirits, is subject to the Government of God, and dependent on His commands (compare Job 2:1) where Satan equally with the sons of God (אלהים בן bên 'ĕlohı̂ym) is said to present himself before God (לחהיצב lehı̂tyatsēb; that is, λειτουργεῖν leitourgein), to minister.
Yahweh uses the ministry of this demon to execute punishment, or when from any other cause it seemed good to him to send evil upon men. But he, although incensed against the race of mortals, and desirous of injuring, is yet described as bound with a chain, and never dares to touch the pious unless God relaxes the reins. Satan, in walking round the earth, could certainly attentively consider Job, but to injure him he could not, unless permission had been given him."
We can know for sure that Jehovah God is in charge of both good and evil spirits to accomplish His purpose. No being is equal with God in heaven and on earth.