Thomas Boston states as regards success and failure in ministry:
“If ministry is unsuccessful it is because God is not in it.”
The thought: You can presume to know where God is working, but you can not presume to know where God is not working.
So do I go here and do that or do I go there and do this?
~ Go where it seems God is working, because your presumption would not necessarily be a bad thing.
What of going where God does not seem to be working?
~ You cannot presume to know where God is not working. (In some sense He is at work everywhere.)
~ You go there if you have a explicit call from God.