My question is addressed to people familiar with religious theology for any monotheistic religion (e.g., Christian doctrine, Islamic doctrine, etc.). For example, I have heard practicing Christians say that "everything that happens is part of God's plan" (particularly when someone dies), and I presume that they include things that happen as a causal result of human action. On the other hand, they also say that God has imposed normative rules for humans to obey (i.e., behavioural rules of what you should and shouldn't do). However, if actions that are contrary to religious ethical laws are nonetheless part of "God's plan", on what basis are they judged to be immoral?
Answers from any monotheistic religious theology are of interest to me, but the question came from hearing things said by Christians. As an applied example, I would appreciate it if answers could address the case of the Romans/Sandhedrin crucification of Jesus Christ. This is the archetypal example of a human action that is said to be part of God's plan, and yet, the people who did it were clearly engaged in murder of an innocent man, contrary to God's law (as set out in Christian doctrine). However, if no-one had killed Jesus, presumably "God's plan" would be thwarted. So, are the Romans/Sandhedrin who murdered Jesus bad, or good, or neither?
Note: To be clear, I am uninterested in critiques of Christianity or any other religion, or arguments for why God doesn't exist. I am already an atheist, so you would be preaching to the choir. What I am interested in is how this issue is resolved under monotheistic religious doctrines that hold these ideas (or something like them).