At first you won't believe that there is anything good can come of the pain. You think pain, you think negative, right? There is nothing positive about this! Why God why, you ask. This process is developing maturity and building faith in you. It takes a huge leap of faith to say to God while suffering "God I don't understand the purpose of the pain, but I trust you to have a purpose in it." This can accelerate your Christian growth like nothing else could. Sounds crazy, but pain is a part of life. It has purpose, power, and it has reason.