In Christ vs Abiding in Christ
2 Corinthians 5:17 Therefore, if anyone is in Christ, he is a new creation; old things have passed away; behold, all things have become new.
John 15:4 Abide in me, and I in you. As the branch cannot bear fruit of itself, unless it abides in the vine, so neither can you, unless you abide in me.
John 15:5 I am the vine, you are the branches. He who abides in me and I in him, it is he who bears much fruit; for without me you can do nothing.