Thematic Bible: Why the body dies

But if Christ is in you, your body is dead because of sin, but the Spirit is your life because of righteousness. Moreover if the Spirit of the one who raised Jesus from the dead lives in you, the one who raised Christ from the dead will also make your mortal bodies alive through his Spirit who lives in you.

But someone will say, "How are the dead raised? With what kind of body will they come?" Fool! What you sow will not come to life unless it dies. And what you sow is not the body that is to be, but a bare seed -- perhaps of wheat or something else. read more.
But God gives it a body just as he planned, and to each of the seeds a body of its own.