That is an excellent question! You are right in saying “Satan is the one striking Job.” In verses 6-7 we that Satan approached God and in verses 9-11 he challenged Him by saying, “Does Job fear God for nothing? Have You not made a hedge around him, around his household, and around all that he has on every side? You have blessed the work of his hands, and his possessions have increased in the land. But now, stretch out Your hand and touch all that he has, and he will surely curse You to Your face” (NKJV)! The Lord responded in verse 12 by saying, “Behold, all that he has IS IN YOUR POWER; only do not lay a hand on his person.” We learn a valuable lesson here. Satan cannot do anything against a believer unless God grants him permission to do so.

In verses 13-19 we see Satan’s vicious attack on Job’s possessions, servants and children. He used “Sabeans and Chaldeans” to steal his livestock and kill his servants (verses 14-15, 17). He used the “fire of God” to burn up his sheep and servants (verse 16). And he used a “great wind” to kill his children. One commentary on this passage summarized it with these words: “Satan has summoned the elements (nature) and men for the destruction of Job’s possessions by repeated strokes. That men and nations can be excited by Satan to hostile enterprises is nothing surprising; but here, even the fire of God and the hurricanes are attributed to him” (Delitzsch on the Book of Job).

As we know from the whole account, the servant who brought Job the news of this mass looting and destruction never mentions Satan, for he knew nothing of Satan’s hand in this. He simply mentions MEN and the FORCES OF NATURE. In the case of MEN, he no doubt thought of them as “thieves and murderers.” And in the case of the FORCES OF NATURE (the “fire of God” and the “great wind”), he most likely thought of these as an “act of God.” The “fire of God” may very well have been “lightning” and we all would normally attribute this to God, just as we would the “great winds” (hurricanes or tornadoes).

What is quite remarkable is Job’s response, for he attributes the CAUSE of his losses to God, yet not in protest or criticism. We read in verses 20-21, “Then Job arose, tore his robe, and shaved his head; and he fell to the ground and worshiped. And he said, ‘Naked I came from my mother’s womb, and naked shall I return there. THE LORD GAVE, AND THE LORD HAS TAKEN AWAY; Blessed be the name of the LORD.” We read that Job “fell to the ground and worshiped” so we know he was not angry at God or blaming Him for anything. We also know that he had no knowledge whatsoever of Satan’s challenge and the permission God gave to Satan to assail him. Job, in faith and deep humility, saw beyond any “second cause.” One has said that “Job saw God as the ULTIMATE CAUSE of his misfortunes, though not the immediate, direct cause, which came from the other participants.” And thus Job acknowledged “the LORD gave, and the LORD has taken away.” In other words, he saw that God is indeed sovereign (in COMPLETE CONTROL of all people and events) and this led him, with a worshipful heart, to thank Him for all that He gives, and to accept from Him all that He takes away. What faith is seen in this! Job had truly “passed the test” that God had allowed Satan to bring to him. This is confirmed in verse 22, “In all this Job did not sin nor charge God with wrong.”

In closing, we can say that “at times” God does allow Satan to use the “forces of nature” to further God’s purposes. In this case God’s purpose was to “prove Job’s faith.” At other times God allows Satan to afflict people with a disease, as we see in the case of the apostle Paul in 2nd Corinthians 12:7, “And that I might not be exalted by the exceeding greatness of the revelations, there was given to me a THORN IN THE FLESH, A MESSENGER OF SATAN that he might buffet me, that I might not be exalted” (DARBY). God, in His sovereignty, used Satan to humble Paul and keep him from becoming proud (though Satan must have thought, as he did with Job, that God’s servant would become angry and rebel against God).  (DO)  (582.3)