Mark 4:35-41 tells the story of Jesus and the disciples crossing the sea when a great storm came up, threatening to capsize the boat. The disciples did everything in their power, but they couldn't control the situation. As a last resort, they turned to Jesus, who was sleeping peacefully through the crisis, asking "Carest thou not that we perish?".
Jesus, of course, rebuked the storm, and settled the disciples.
This is an important lesson. When they were caring about their problems, and trying everything in their power to solve it, they found that their own efforts were not adequate. They had to turn to the Lord, who was quietly resting; letting them prove to themselves just how unempowered they were, and how they did not need to worry when He was around to take care of it.
That is an important principle for us today, too. While we must take responsibility for our actions, we must never try to take control. Only God is big enough to take control.
Here is the principle in action: When we care about things and try to control them, He rests, and lets us mess things up. When we give up and let Him take control, we then can rest.
We care, He rests.
He cares, we rest.