from Spurgeon's sermon, "The Spur" #943. John 9:4

A young convert, after finding peace with God, was
heard to say, "I rejoice that I was a lost sinner."

Strange matter to be glad about, you will say,
for of all things it is most to be deplored; but
here was her reason: "Because God's infinite
grace, and mercy, and wisdom, and all His
attributes, are glorified in me as they never
could have been had I not been a sinner and
had I not been lost."

God has allowed moral and physical evil to come
into this world to cause His infinite wisdom, grace,
power, and all His other attributes, to be the better
seen by the whole intelligent universe.

Sin, somehow or other, desperate evil as it is,
will be overruled to display God's goodness.

Were there no sin there had been no Savior;
  if no death, no resurrection;
  if no fall, no new covenant;
  if no rebellious race, no incarnation, no
Calvary, no ascension, no second advent.

Though we do not know, and perhaps shall
never know the deepest reason why an infinitely
gracious God permitted sin and suffering to
enter the universe, yet we may at least be
encouraged this practical thought: God will be
glorified in the overcoming of evil and its
consequences.