17th century Puritan, Jeremiah Burroughs offers this:
...the peace of God is not enough to a gracious heart except it may have the God of that peace. A carnal heart could be satisfied if he might but have outward peace, though it is not the peace of God; peace in the state, and his trading, would satisfy him. But mark how a godly heart goes beyond a carnal. All outward peace is not enough; I must have the peace of God. But suppose you have the peace of God, Will that not quiet you? No, I must have the God of peace; as the peace of God so the God of peace. That is, I must enjoy that God who gives me the peace; I must have the Cause as well as the effect. I mus see from whence my peace comes, and enjoy the Fountain of my peace, as well as the stream of my peace. And so in other mercies: have I health from God? I must have the God of my health to be my portion, or else I am not satisfied. It is not life, but the God of my life; it is not riches, but the God of those riches, that I must have, the God of my preservation, as well as my preservation...
"Whom have I in heaven but thee, and there is none upon the earth that I desire beside thee."
(excerpt taken from The Rare Jewel of Christian Contentment)