I don't agree with that.
Part of the Lords Prayer is "let your will be done on earth as it is in heaven" That means that God's will is happening in heaven but not on earth.
I don't believe that pain, suffering, murder, and all the rest of the messed up shit that happens on earth is part of Gods will. I think people make up theology to try to comfort people, which is stupid. How can you tell a mom that just lost her child that it is part of Gods will. I'd be pissed at God if it were true.