When I was in seminary, one of my professors used to tell us that the most basic prayer we had to learn was to walk outside, look up and say, "You are God, and I am not." I think that prayer was first uttered by one of the saints, but I could not figure out which one. The point is we have to stop trying to do God's job and focus instead on worshipping rightly, and doing what he's asked of us. We have to believe with our minds, hearts and actions that God is sovereign in every situation.
For the ancient Israelites, they had to realize that God is sovereign over their lives and longed to deliver them from oppression. They had to be ready to give up the relative comfort of their lives in Egypt in order to be free from slavery and to take possession of the land that God had in mind for them. They had to be convinced that God could take them out of Egypt, through the desert, and provide for their needs and safety. God is sovereign over oppression and faithful in providing.
For the Pharisees, they had to realize that God is sovereign over the Sabbath. Now, of course, they mostly never got this or they never would have crucified Jesus, but that was the word that Jesus was preaching to them. God made the Sabbath and could observe it as he saw fit; human customs did not fulfill the Sabbath's demands. If God wanted to provide for the hunger of his faithful ones on the Sabbath, then God had a right to do that. But the Pharisees were unable to see that Jesus was much greater than the temple. But God is still sovereign over our customs and faithful in providing.
What is it that we have to let go of in order to let God be God in our lives? What is so comfortable to us that we refuse to let go of it, regardless of how destructive it is to our spiritual lives and how great an obstacle it is to our relationship with God? Maybe we want God to answer a particular prayer in a particular way, and God is offering us something better. If so, we need to let go of our own ideas of how God's will must be accomplished in order that we might see where he is leading us. God is sovereign over our lives and is faithful in providing. But we must be willing to say, "You are God, and I am not."