As Paul mentions in this chapter, the last enemy to be defeated is "death." Indeed this is true in the physical realm, for " For to me, to live is Christ and to die is gain." Phil. 1:21 And truly then, those who have died an earthly death "in Christ," will then live with Him eternally. What I would like to point out, however, is that we "die daily." God is in the process of bringing us unto "death" in Him, so that through this process, we are then being made perfect. We are then being made into His image. The process of dying unto one's self, is not the ultimate end, but that we would then become resurrected into His image.
 Or don't you know that all of us who were baptized into Christ Jesus were baptized into his death?  We were therefore buried with him through baptism into death in order that, just as Christ was raised from the dead through the glory of the Father, we too may live a new life.
RO 6:5 If we have been united with him like this in his death, we will certainly also be united with him in his resurrection.  For we know that our old self was crucified with him so that the body of sin might be done away with, that we should no longer be slaves to sin--  because anyone who has died has been freed from sin.
Now as it is written, "He has put everything under his feet," and the last enemy to be defeated is "DEATH." This is the ever-present awareness that death is "in us." We walk around with it everyday. We are very much familiar with our "old nature." We seem to battle with it daily. However, it is good to note that it is "sin in us," it is not us. As we are being conformed into the image of Christ, through the process of dying unto ourselves, our nature then becomes resurrected, if you will. Not only do we await the resurrection of the dead through Christ (PHYSICALLY) but we can see this process at work now even DAILY. And then when finally this last enemy of DEATH is defeated "in us," then Christ will rule. He not only will rule here on earth, but will rule in our bodies as well.
Then the scripture which so eloquently states below will be accomplished:
 When the perishable has been clothed with the imperishable, and the mortal with immortality, then the saying that is written will come true: "Death has been swallowed up in victory."
55 "Where, O death, is your victory? Where, O death, is your sting?"
The sting of death is sin, and the power of sin is the law.  But thanks be to God! He gives us the victory through our Lord Jesus Christ. I Co. 15
We are victorious, we are not defeated. No matter what comes our way during this lifetime, we can be assured that we will be "more than conquerors." Remember that there is NOTHING on this earth, no DEATH, no PERIL, no FAMINE, no DISEASE, or POWER of any kind, that can separate us from His love.
RO 8:37 No, in all these things we are more than conquerors through him who loved us.  For I am convinced that neither death nor life, neither angels nor demons, neither the present nor the future, nor any powers,  neither height nor depth, nor anything else in all creation, will be able to separate us from the love of God that is in Christ Jesus our Lord.