God changes us from the inside out, and we live the rest of our lives knowing we are here for a reason.
No matter what problems you may face, God has a way to make them purposeful. God helps us change our perspective so that we see problems as opportunities.
There are many things that aim to undermine our faith: our guilt, different diagnoses, depression, anxiety, fear, and various circumstances. God wants to build our faith and confidence to be so strong it can handle anything thrown our way.