hat or who is it that died? It was Paul's Adamic "I" that died. Paul's connection to Adam was what brought the death sentence upon him. "Therefore, just as through one man sin entered into the world, and death through sin, and so death spread to all men" (Rom. 5:12). Paul's Adamic "I" was mortal on account of Adam's sin, because this "I" was under the authority and headship of Adam.

For a full reading :

https://godskingdom.org/studies/books/pauls-epistle-to-the-saints-in-rome-book-1/chapter-10-the-two-is