Marbles,
Your questions can be answer from various theological perspectives and schools of thought. But understanding such answers and the reasons is not so easy to understand. For example, Talmudic Judaism teaches that angels don’t have free will in-spite of Rashi’s commentary on Gen 6:2. Rashi offers 2 explanations for benihaelohim. Talmudic Judaism prefers one because that is the same explanation Ramban uses in his commentary when he refers to Rashi—but even so, Rashi’s hated explanation for the verse is nonetheless still valid. Therefore, Talmudic Judaism concludes that Satan is a holy angel doing his job as prosecutor in God’s Court— sort of speak. And that evil comes from God even though He is holy—imagine that. Therefore, some Rabbi’s have commented that the holocaust came from God—imagine that. Christianity teaches that Satan is the source of evil although God sometimes allows evil to happen to his servants.
Talmudic Jews base their logic on the premise that the oral law us inspired. The Talmud stands on its own merit and cannot be debunked even with Tanakh whereas the Christian Scriptures depend on the OT and integrates itself with the OT.
For example, the Tannaim comment that the only sin king David committed relating to Uriah was not consulting with the sanhedrin and that king David did not murder Uriah. It uses sophistry in my opinion to argue that Uriah had slighted the king authorizing the king to execute Uriah and that during war married women became divorced from their husbands authorizing king david to sleep with Uriah’s wife in-spite of what Nathan told King David about his sin. Christianity though, refers to Bathsheba as the wife of Uriah. The christian scriptures interpret the OT based on context, literary device of the ot, teachings of Jesus whereas the Talmud interprets the Bible as an authority regardless of context and text implications.