As obedient children, do not be conformed to the passions of your former ignorance, but as he who called you is holy, you also be holy in all your conduct, since it is written, “You shall be holy, for I am holy.”
1 Peter 1:14-16
I should want to be holy as God, my Father, Who saved me through His Son, and enables me through His Holy Spirit is holy. In my obedience as God's child, holiness should result in my life. I should live differently as God's child than I did when I was without God. I should seek to reflect His holiness and glory in this world. I should be holy as Christ lives in me through His Spirit. I should be holy for God is holy.
But there is a constant drag on this noble call to holiness. Peter calls it the passion of my former ignorance (agnoia - literally "not knowing"). This means that I sin because at one time I did not know anything better and I can revert to that sort of condition if I am not careful. But now I know God and His call to be holy. So I must not revert to conforming to my past sinful patterns. Even though I am most comfortable in unholiness, that is no excuse to disobey what I now know. I must obey the call to live as God shows me in His Word.
I see the holiness of Christ in the scriptures. I read the specific sins to put off and the character of my Savior that I must put on. And the Holy Spirit convicts me of sin, guiding me gently yet firmly in the truth of scripture. The Spirit enables me to obey as God's child so that clothed in the righteousness of the Son I can obey the Father's call to be holy as He is holy.