For our light affliction, which is but for a moment, is working for us a far more exceeding and eternal weight of glory -2 Corinthians 4:17

A ship that has large sails and a fair wind, needs ballast. Troubles are the ballast of a believer…(T)here is such a thing as making troubles raise me towards heaven. A gentlemen once asked a friend, concerning a beautiful horse of his, feeding about in the pasture with a clog on its foot, “Why do you clog such a noble animal?” “Sir,” said he, “I would a great deal sooner clog him than lose him: he is given to leap hedges.” That is why God clogs His people. He would rather clog them than lose them; for if He did not clog them, they would leap the hedges and be gone. They want a tether to prevent their straying, and their God binds them with afflictions, to keep them near to Him, to preserve them, and have them in His presence. Blessed fact-as our troubles abound, our consolations also abound.

Then one word with you who are almost driven to despair…There is a man here quite despairing-almost every hope gone… Thou hast fallen off the main deck, thou art in the sea, the floods surround thee; thou seemest to have no hope; thou catchest at straws; what shalt thou do now? Do? why lie upon the sea of trouble, and float upon it; be still, and know that God is God, and thou wilt never perish… for behold the life-boat cometh; Christ is coming to thy help; soon He will deliver thee, and fetch thee out of all thy perplexities. ~ C.H. Spurgeon

http://www.blueletterbible.org/Comm/spurgeon_charles/sermons/0013.cfm