You are a new creation!
That is what the Scriptures tell us and it matters. It matters because it describes the transformation we have undergone and are undergoing. You cannot declare Jesus as your Lord and stay the same. We had to be changed because we have become the vessels of the Spirit of God. We cannot be one with Yahweh and stay the same.
This means that our perspective, attitude and understanding of life are also transformed. This impacts us in many ways. Just to name a few, our compassion increases, our actions become rooted in love, our possession by possessions is broken so we easily act in generosity with the things we have been loaned. It is not as the world teaches, that acts of love and kindness change our heart, but instead that our transformed heart changes our actions.
Knowing and living this makes it easier for us to understanding the Scriptures that warn us of such things as:
"Wherever there is jealousy and selfish ambition, there is disorder and everything that is evil." (James 3:16)
It would be fantastic if our transformation was complete but it is an ongoing thing. Let's understand it this way: The capacity for this transformation is complete, so we are capable of great spiritual growth, but we have to grow into that capacity. There will be days that we fail and allow the old nature of jealousy and selfish ambition to undermine the work of the Spirit. But the nature of our relationship with Father (because of Jesus) is such that, by his grace, we can confess it, repent of it and release it because it was already forgiven on the cross. But don't dismiss it so quickly yet.
Jesus came to destroy the work of the enemy in all its forms. Before he ascended he told us that all authority in heaven and on earth has been given to him, and then he sent us out in this authority. He gave us the same mission Father gave him: To destroy the works of the enemy. That is our purpose here.
Such works include but are not limited to sin, illness, any form of brokenness, which includes things like jealousy and self ambition. You have been given authority in Jesus to destroy these works. Wherever they exist disorder and evil exists. You are a warrior, a mighty warrior in the Lord, and it has been given to you to destroy all strongholds of the enemy, and that includes the ones that try to take root in you.
Your heart and mind are not in control; they are subject to the Holy Spirit. If you give them control then your emotions and intellect will always lead you back to the old nature. They need us to keep them subjected to the Spirit of God. That is the oneness we have with him. If you think you are in charge you are in trouble. If your emotions are given free reign, you are in trouble. Jesus speaks to our spirit and our spirit speaks to our mind and heart, and as warriors we keep our heart and mind in submission to his commands. In this way we are mighty Kingdom warriors, destroying the works of the enemy wherever we are in the moment.
We are not what we were; we are a new creation.