I am sure that just about anyone that has ever even contemplated God has had to struggle with this question. To put in the context of the story. "Lord, if you are an all powerful and loving God and Sonya is a beloved daughter of your then why must she suffer in dire poverty and prostitution living with no hope? Lord where are you, why don't you help her, and why does such suffering occur on this earth?"
Ah... who hasn't struggled with this question? I am a Christian, my father is not. He said to me once, "I am willing to believe in God every time I look at the universe and can accept the idea that it took an omnipotent being to create it. But if He refuses to be all good and allows innocent people to suffer, then I have no time or desire to follow Him."
It is the monumental struggle of humanity's ability to be God's servants. And it is one that FD does not shy away from. C&P is only one example. He has helped me come to terms with this struggle in my own life, although to be honest, it is a struggle that still wracks me when I see the enormous suffering throughout our world.
I have come to believe that first and foremost, we are to follow God because He desires it. The servant serves without regard to his own wants or sense of righteousness. The servant serves because he trusts that his master knows best, even when he doesn't understand the choices his master makes. I believe that Sonya and the many others like her in FD's work, follow God first, because they accept that they are His servants, and that He knows best.
Second, I believe that happiness or its pursuit are not, contrary to my own Declaration of Independence, endowed in me by God. It is probably not a uniquely American thing by any stretch, but it is certainly an American trait, that we feel that our rewards in life should match our merits, good or ill. And that the concept of bad things happening to good or innocent people, is antithetical to the foundations of our society and to the foundations of God's character.
I believe, perhaps, that God, the father, may be more the watchmaker. The one who put this vast and beautiful universe into place and who watches what we do in it a bit form afar, tinkering as necessary to make sure it runs reasonably well, but not perfectly. I believe that Jesus and the Holy Spirit are the father's gifts to us, to help us understand our role in this universe, to guide us when we have to choose one path over another, and to comfort us when our choice, or circumstances beyond our choice, cause us to suffer.
I believe that in suffering and in evil and those things that in our hearts we just do not find to be compatible with a loving God, we are to be His servants and help to relieve that suffering and fight that evil, as He desires. We are to find true servanthood in striving to make the world more beautiful than it is, to be a better place because we are in it. It stretches my innate concept of what a Good God is, that He would leave much of that work up to a wholly imperfect and weak servant such as me.
I think this is the fundamental issue that FD forces us to explore in the character of Sonya. Life is our responsibility; good is not always as we would expect it to be defined, God is "my refuge and my strength" as the psalm goes, but not always there to intercede. We are to follow Him because we are made to be His servants; we are to find joy in adding beauty to a sometimes ugly world. And we are to find comfort in the arms of Jesus, who's sacrifice for the suffering in this world is ultimately meant for us as well.