New Creation; New Mind; New Life

Being a new creation involves a renewing of the mind.  When you accept Christ as Saviour and Lord the Bible says you become a new creation. 
"Therefore, if anyone is in Christ, he is a new creation; the old has gone, the new has come!" 2 Corinthians 5:17

When you become a new creation, you cannot bring your old way of thinking and your old ideas and paradigms into your new life.  You have become a new creation, which includes a new mind; a new way of thinking.  You need to learn and be trained in the new way of thinking (through studying God's Word, conversation with God - prayer, fellowship with believers, biblical teaching...) This is the way to start your new life; by renewing your mind in the way you see and think of things. A renewed mind will affect your focus, your choices and how you live your new life.
"Do not conform any longer to the pattern of this world, but be transformed by the renewing of your mind. Then you will be able to test and approve what God's will is—his good, pleasing and perfect will." Romans 12:2

Bringing parts of your "old self/sinful nature" into your new life will not work.  It will draw you back to your old life.  You must "throw-off" every part of the "old, self-serving nature" in order to live and grow in the new life...

"Those who live according to the sinful nature have their minds set on what that nature desires; but those who live in accordance with the Spirit have their minds set on what the Spirit desires. The mind of sinful man is death, but the mind controlled by the Spirit is life and peace; the sinful mind is hostile to God. It does not submit to God's law, nor can it do so. Those controlled by the sinful nature cannot please God." Romans 8:5-8

In His Love,
Rosa