2 Corinthians 5:17 Therefore if any man be in Christ, he is a new creature: old things are passed away; behold, all things are become new

Galatians 6:15 It doesn’t matter whether we have been circumcised or not. What counts is whether we have been transformed into a new creation.

We have received the opportunity to be a new creature, but that does not mean that old desires or temptations won’t arise. Our role in being new is to be in Christ. We have a choice to be transformed. That means we make continuous decisions to operate as He would. So, when situations arise we choose to be in Christ, taking on our transformed nature.