Nor are other Christian truths safe from this mess. The sacraments of Communion and baptism suffer because they become merely movements of matter in this Gnostic understanding of Christianity. Yet many Christians believe this. Believers may have differing views of the sacraments and their efficacy, but there is no doubt that denial of God's involvement with matter is heretical. In doing so they are denying the only objective communication they have from God.
Evangelism suffers as well.
If we do not know the philosophies that shape our world-view, it is nearly impossible to communicate the gospel to other minds. Perhaps we don't want to be seen in the company of worldly people anyway. Serious Christians might question our spirituality if we know too much about the world. Besides, it might ruin our witness. How we understand ourselves is also affected.