The Bible teaches the whole of human personality is that of spirit and flesh. One of the forty-seven verses that teach this dualism is Ps 63:1, “My soul thirsts for You, my flesh yearns for You.” Of our two parts which one is more important?
If the flesh is more important to one’s life then one spends their life minding the things of the flesh. Such a life is limited, near-sighted, and deaf to the voices of eternity, for every attempt to satisfy the flesh ends with a thirst for more; a burning desire with no satisfaction.
The person of the spirit recognizes their finality is not dust, but that God has wrapped their eternal spirit in a temporal shell, and when the temporal is gone the spirit goes on. Therefore, fulfillment in life comes from answering the call of the spirit.
What do you think of death? If you live for the flesh you should be afraid, for at death your spirit passes into eternity unclothed with its unquenchable desires of the flesh. If you live for the spirit you are not afraid, for you step off this mortal ball clothed in Christ and enter into God’s eternity.