That's the reason Christians exist. To glorify God. Well Peter is not talking about having joyful praise songs in church. He is not as concerned with what we do in the one or two hours during which we meet on a Sunday, as he is with the other one hundred and sixty six hours of the week.
Church is vitally important.
You should make meeting with God's people your highest priority. But it only represents about half of one percent of your total time. Now just in case we become legalistic and proud of our efforts to live godly lives in the world, he surrounds these verses with a reminder of God's grace. And at the end of this section, in verses 21 to 25, he reminds us that our salvation is not based on living a godly life, but solely on the death of Christ for our sins. Dear friends, I urge you, as aliens and strangers in the world, to abstain from sinful desires, which war against the soul.