John 14:21

He who has My commandments and keeps them, it is he who loves Me. And he who loves Me will be loved by My Father, and I will love him and manifest Myself to him.

When we believe in something, we trust and follow what it says. We believe in things every day without thought. It is the same with the commandments of Jesus when we are sold out to God; we should follow His commandments and keep them. Not because we have to, but because we believe in Jesus. We know the benefits for our lives and so that Jesus can manifest Himself to us.