As he is holy, so you, too, be holy in all your conduct. 1 Peter 1:15
Since Scripture says : Be holy for I am holy (1 Peter 1:16), so imitate the one who called you and be holy in all your conduct. Remember that we were freed from the useless way of life of our fathers, no with gold and silver but with the precious blood of the Lamb without spot or blemish. Through him, you have faith in God who raised him from the death. In raising Jesus Christ from the dead, he has given us new life.
In this new life, we have gained interior purification as being born anew, being born from above, which Jesus tells Nicodemus to bring about a change within himself. That, too, is what we need. What follows is a call to live perfectly : not attached to the things of the present, but eager to live a useful and holy life before God.
This word is the Gospel which has been brought to us : All flesh is grass and its glory like the flowers of the field. The grass withers and the flower falls, but the word of the Lord endures forever. Love one another, there with all your heart, since we are born anew, not from mortal beings, but with enduring life, through the word of God who lives and remains forever.
So give up all evil and deceit, hypocrisy, envy and all kind of gossip. Like obedient children, do not return to our former life given over to ignorance and passions. Live a blameless life in obeying the truth so that people may see the good work we do and give glory to God, the one who calls us to be holy in all our conduct.
Man exists for the holiness and glory of God.