To the best of our knowledge the author of the Book of Job wrote his book before Moses penned Genesis through Deuteronomy. Therefore, Job had absolutely no copy of any Old Testament book to refer to in order to gain his knowledge of God. That had to come to him directly from the Spirit of God and from Job's own personal experience. Job found great comfort and security knowing that God was well aware of his situation. And Job went even further to express his understanding that the testing he was experiencing came by way of God's approval and plan.
There's nothing in the Book of Job to suggest that he even considered Satan's involvement when he began to face his trials. Actually, according to this verse, he was convinced that God was working out His will and that Job would ultimately benefit saying he would "come forth as gold." A similar thought is expressed in 1 Peter 1:7, "that the genuineness of your faith, being much more precious than gold that perishes, though it is tested by fire, may be found to praise, honor, and glory at the revelation of Jesus Christ." And it is also stated in James 1:2, "My brethren, count it all joy when you fall into various trials."
The lesson here is that God is at work in our lives even when we face severe trials and hardships. God is not only doing this for His own glory, but also for the spiritual enrichment of our lives. If through trials you are made "more like Christ" then may you see the outcome of suffering is to assure that you, too, will "come forth as gold."