whom not having known you love; in whom, though now you don't see him, yet believing, you rejoice greatly with joy unspeakable and full of glory--
What is your part? Just believing. You know, God's done all the work. He didn't leave anything as important as the work to someone as weak as you. You'd mess it up. So God did all the work and all that is left for you to do is to believe the work of God.