The Color Purple is an epistolatory novel, meaning that each chapter takes the form of a letter, many of which in this instance are addressed to God. The novel's protagonist, Celie, begins writing letters to God because she is told that, "You better not never tell nobody but God. It'd kill your mamy."
In the opening letter of the novel, Celie, who has grown up in Georgia and suffered much abuse, asks God to "give [her] a sign letting [her] know what is happening to [her]." At this point, Celie, who is fourteen years old, is pregnant with her second child and the victim of rape and incest at the hands of her father, Alphonso.
In her third letter, Celie describes how her father berates her for not looking "decent," and asks in return, "What I'm sposed to put on? I don't have nothing." This question is addressed as much to herself as to the God to whom she writes. She receives no satisfactory answer from either herself or from God.
After this point, Celie doesn't ask direct questions of God, but the description of abuses and injustices that she continues to describe in her letters implies an ongoing reaching out for answers and for succour. When those answers continue to fail to come, and God becomes conspicuous by his silence and his absence, Celie stops writing to God, asking her sister, Nettie, "What God do for me?" Celie also says that the God she has been writing to "is a man. And act just like all the other mens [she] knows. Trifling, forgitful and lowdown."