I just finished reading "The Problem of Pain" by C. S. Lewis and I recommend it. Here are just a few of my favorite quotes from the book. I've noted what chapter they are from because your copy of the book may have different page numbers.
On Divine Omnipotence
"The freedom of God consists in the fact that no cause other than Himself produces His acts and no external obstacle impedes them... that His own goodness is the root from which they all grow and His own omnipotence the air in which they all flower."
On Divine Goodness
"The Divine 'goodness' differs from ours, but it is not sheerly different: it differs from ours not as white from black but as a perfect circle from a child's first attempt to draw a wheel."
"To ask that God's love should be content with us as we are is to ask that God should cease to be God:... He must labor to make us lovable."
On Human Wickedness
"Christianity now has to preach the diagnosis... in itself very bad news... before it can win a hearing for the cure."
"We have a strange illusion that mere time cancels sin... The guilt is washed out not by time but by repentance and the blood of Christ:... All times are eternally present to God."
On The Fall of Man
"Our present condition, then, is explained by the fact that we are members of a spoiled species."
On Human Pain
"We are not merely imperfect creatures who must be improved: we are, as Newman said, rebels who must lay down our arms."
"The human spirit will not even begin to try to surrender self-will as long as all seems to be well with it."
"God whispers to us in our pleasures, speaks in our conscience, but shouts in our pains: it is His megaphone to rouse a deaf world."
"As St. Augustine says somewhere, 'God wants to give us something, but cannot, because our hands are full... there's nowhere for Him to put it.' Or as a friend of mine said, 'We regard God as an airman regards his parachute: it's there for emergencies but he hopes he'll never have to use it."
"I call this a Divine humility because it is a poor thing to strike our colors to God when the ship is going down under us; a poor thing to come to Him as a last resort, to offer up 'our own' when it is no longer worth keeping. If God were proud He would hardly have us on such terms: but He is not proud, He stoops to conquer, He will have us even if we have shown that we prefer everything us to Him and come to Him because there is 'nothing better' now to be had... It is hardly complimentary to God that we should choose Him as an alternative to Hell: yet even this He accepts."
On Human Pain, continued
"... suffering is not good in itself."
"Our Father refreshes us on the journey with some pleasant inns, but will not encourage us to mistake them for home."
"He (the sinner) has his wish... to live wholly in the self and to make the best of what he finds there. And what he finds there is Hell."
"To enter heaven is to become more human than you ever succeeded in being in earth; to enter hell, is to be banished from humanity."
"I willingly believe that the damned are, in one sense, successful rebels to the end; that the doors of hell are locked on the inside."
On Animal Pain
(Because this is funny)
"'Where will you put all the mosquitoes?'... a question to be answered on its own level by pointing out that, if the worst came to the worst, a heaven for mosquitoes and a hell for men could very conveniently be combined."
"Your place in heaven will seem to be made for you and you alone, because were made for it."
"Heaven is a city, and a Body, because the blessed remain eternally different:"
Here's a link to buy the book if you want to today.