Prayer is not passive. It requires faith and belief yes maybe but you are asking someone/thing else to do the work for you rather than doing it yourself
Not necessarily, within Christianity there is the belief that most often the result requires action to be taken by yourself. That God works through people.
As for discipline and control - I am guided by my own ethical compass. I have a line over which I won't tread but otherwise if it's something I would do non magically then I have no problem with doing it magically.
Yes, but ethical compasses do not give a person the power of being able to see into the future or how exactly a spell will manifest. If there is a belief it will manifest. Again back to the idea of popular time travelling narratives.
No difference from non magical life really
But in non magical reality, unexpressed, unspoken (to the people involved) thoughts, without direct (as in non ritual) action, do not, generally, effect life events or people. Courts prosecute on actions not thoughts that remain thoughts, no matter how focussed.
In this way it is easier for a dabbler or novice not to take it seriously enough to prepare themselves and truly think about the consequences. And even with all the knowledge and experience of lifetimes and years spent studying the craft, I do not know how someone is able to truly spend enough consideration in terms of altering the course of events supernaturally. And how do thoughts not begin to just leak into the ether, spells being cast accidentally, without forethought, once the skill of magical focussed thought is gained and becomes second nature?
So that is why I'm more comfortable with the idea of accepting divine governance.