It is the Spirit who gives life; the flesh is no help at all. The words that I have spoken to you are spirit and life. John 6:63 ESV
The antithesis between "flesh" and "spirit" occurs frequently in the Bible, which always reminds us of the conflict between the sensual realm and the Spirit realm. Meaning we should surrender all of our being completely to the Spirit because He is the only source of life, for the flesh have nothing to offer to it subject. Christ have revealed the source of the Spirit to us, it is the WORD. The word is the effulgence of God's glory, the effluence of His Spirit. Every good thing you can ever think of are in God's word: life, peace, joy, health, prosperity etc. For God's word is a complete package for the thirsty man.