Staff Member on LOA
In Leadership, Ben Patterson, dean of the chapel at Hope College and a former pastor, writes:

In the spring of 1980 I was suffering great pain from what was diagnosed as two herniated discs in my lower back. The prescription was total bed rest. But since my bed was too soft, the treatment ended up being total floor rest. I was frustrated and humiliated. I couldn't preach, I couldn't lead meetings, I couldn't call on new prospects for the church. I couldn't do anything but pray.
Not that I immediately grasped that last fact. It took two weeks for me to get so bored that I finally asked my wife for the church directory so I could at least do something, even if it was only pray for the people of my congregation. Note: it wasn't piety but boredom and frustration that drove me to pray. But pray I did, every day for every person in my church, two or three hours a day. After a while, the time became sweet.
Toward the end of my convalescence, anticipating my return to work, I prayed, "Lord, this has been good, this praying. It's too bad I don't have time to do this when I'm working."
And God spoke to me, very clearly. He said, "Stupid (that's right, that was his very word. He said in a a kind tone of voice, though). You have the same twenty-four hours each day when you're weak as when you're strong. The only difference is that when you're strong you think you're in charge. When you're weak you know you aren't."

Prayer is an admission of weakness and the single most important expression of true dependence on God.

Dependence, Ministry, Prayer
2 Cor. 12:8-10