Although some people mistakenly attribute the quote above to C.S. Lewis's book Mere Christianity, Lewis never wrote that. If you are a Christian, I would caution you that the belief you just expressed is very close to the dangerous heresy of Manichaeism. This was the heresy that St. Augustine took many years to break free of. As Christians who profess the Nicene Creed, we believe that God gives us both a body and a soul and that both, while tarnished by sin, are good and that we will be returned to our earthly body at the end of time.
The Book indicates something else:
Romans 7:5
For while we were in the flesh, the sinful passions, which were aroused by the Law, were at work in the members of our body to bear fruit for death.Romans 8:5-9
For those who are according to the flesh set their minds on the things of the flesh, but those who are according to the Spirit, the things of the Spirit. For the mind set on the flesh is death, but the mind set on the Spirit is life and peace, because the mind set on the flesh is hostile toward God; for it does not subject itself to the law of God, for it is not even able to do so,and those who are in the flesh cannot please God. However, you are not in the flesh but in the Spirit, if indeed the Spirit of God dwells in you. But if anyone does not have the Spirit of Christ, he does not belong to Him.Romans 13:14
But put on the Lord Jesus Christ, and make no provision for the flesh in regard to its lusts.1 Corinthians 15:50
Now I declare to you, brothers, that flesh and blood cannot inherit the kingdom of God, nor does the perishable inherit the imperishable.Galatians 5:17
For the flesh sets its desire against the Spirit, and the Spirit against the flesh ; for these are in opposition to one another, so that you may not do the things that you please.Galatians 5:19-21
Now the deeds of the flesh are evident, which are: immorality, impurity, sensuality, idolatry, sorcery, enmities, strife, jealousy, outbursts of anger, disputes, dissensions, factions, envying, drunkenness, carousing, and things like these, of which I forewarn you, just as I have forewarned you, that those who practice such things will not inherit the kingdom of God.Galatians 5:24
Now those who belong to Christ Jesus have crucified the flesh with its passions and desires.Galatians 6:8
For the one who sows to his own flesh will from the flesh reap corruption, but the one who sows to the Spirit will from the Spirit reap eternal life.Galatians 6:12-13
Those who desire to make a good showing in the flesh try to compel you to be circumcised, simply so that they will not be persecuted for the cross of Christ. For those who are circumcised do not even keep the Law themselves, but they desire to have you circumcised so that they may boast in your flesh.Ephesians 2:3
Among them we too all formerly lived in the lusts of our flesh , indulging the desires of the flesh and of the mind, and were by nature children of wrath, even as the rest.
1. I believe in one God, the Father almighty, maker of heaven and earth, of all things visible and invisible.
2. I believe in one Lord Jesus Christ, the Only Begotten Son of God, born of the Father before all ages.
3. God from God, Light from Light, true God from true God, begotten, not made, consubstantial with the Father; through him all things were made.
4. For us men and for our salvation he came down from heaven, and by the Holy Spirit was incarnate of the Virgin Mary, and became man.
5. For our sake he was crucified under Pontius Pilate, he suffered death and was buried, and rose again on the third day in accordance with the Scriptures.
6. He ascended into heaven and is seated at the right hand of the Father.
7. He will come again in glory to judge the living and the dead and his kingdom will have no end.
8. I believe in the Holy Spirit, the Lord, the giver of life, who proceeds from the Father and the Son, who with the Father and the Son is adored and glorified, who has spoken through the prophets.
9. I believe in one, holy, catholic and apostolic Church.
10. I confess one Baptism for the forgiveness of sins and I look forward to the resurrection of the dead and the life of the world to come.