Why have faith? The question really is: WHY NOT?
Faith gives you determination not to give up on yourself. Faith helps you to stay positive. When goodness overcomes evil, and light overcomes darkness, faith is the operative force.
Acknowledging God's presence begins a pouring out of peace. Faith brings courage to realize that you are greatly loved.
Faith helps you to make difficult decisions that are not so popular, but needs to be done for your mental health. Faith is trusting that God will take care of things. God wants you to be happy; hope does not disappoint.
Answer: Having faith brings benefits, brings hope, brings resilience and brings happiness.