Testing Job

Why does God test us when God should know our faith? I just finished reading the book of Job and there are many similarities and differences from this book compared to other books in the Old Testament. The book of Job is like the story of Adam and Eve because Satan was involved in both stories because in the book of Job, Satan was involved in making him suffer and in Adam and Eve he was involved in the temptation. Another similarity is that in the book of Job the Lord tested Job and the Lord also tests Adam and Eve in the Garden of Eden. In both books they also "fail" the test given because Job cursed out God after he was suffering from sores and didn't stay faithful and Adam and Eve ate from the tree they were not supposed to eat from. The book of Job is different than the story of Adam and Eve because Job was inflicted with pain and suffering during his test, but Adam and Eve weren't. The book of Job also had more feelings and "show don't tell" than the other books of the Old Testament. Another difference is that Job's was a test of his faith, but Adam and Eve's was a test of if they follow God's commands. God is always testing us to see if we actually are faithful, but does God really need to? God knew Job was faithful, but after Job cursed him out, I wonder if God still thinks he's faithful.