This is how Charles Haddon Spurgeon explained what it means to die with Christ:
I suppose that, if you were to meet your old self, he would hardly know you, for you are so greatly altered. I dare say he would say to you, “Come, old fellow, let us go to the theater, or turn into this beer-shop, or let us go home, and find out some way of amusing ourselves.”
You would reply, “No, sir; I cut your acquaintance a long time ago, and I do not mean to have anything further to do with you, so you may go about your business as soon as you like. I am not what I was, for I have been crucified with Christ, and I am dead, and my life is hid with Christ in God.