Danoh, what if the Jews repented and accepted Christ and there was no stoning of Stephen? What do you think would have happened in God's plan?
Feel free to ask yourself that question; see what it allows the seeing of.
And while you are asking it of yourself; observe how you go about attempting to solve for its answer; observe both what principles you appear to either follow and or break.
As you do, write them down to yourself; worded as a principle....
'Okay, what principle or principles, does (Moses; the Lord; Paul; or whomever) appear to be following here?' And or 'what principle or principles does this writer appear to be basing his assertions on, here; in this passage?'
Write out your findings to yourself worded as principles you can then rely on and or avoid consciously...
I constantly do this kind of thing.
It's been a great resource whenever I have sought to study out one thing or another...