After purusing several scholarly writings, I turned to the new Catholic Commentary on Sacred Scripture series, on whose editorial board I serve, to see how Mary Healy handled the passage in her commentary The Gospel of Mark (Grand Rapids: Baker Academic, 2008). In addition to the scholarly background, Dr. Healy touches on the implications for our faith today, cites the Catechism of the Catholic Church and offers in the sidebar called "Living Tradition" a quotation from Tertullian's The Resurrection of the Flesh, called the "Flesh as the Hinge of Salvation" (p. 147):
The importance of the flesh in God's plan for salvation was a continual source of wonder to early pagan converts to Christianity, especially those steeped in Greek philosophy, which had often disparaged the body.
Tertullian, a third-century Father, wrote eloquently about how it is through our flesh that Christ mediates his grace in each of the sacraments:"The flesh is the hinge of salvation... The flesh is washed so that the soul may be made clean. The flesh is anointed so that the soul may be consecrated. The flesh is signed so that the soul may be protected. The flesh is overshadowed by the laying on of hands so that the soul may be illumined by the Spirit. The flesh feeds on the body and blood of Christ so that the soul too may be filled with God. (Flesh and spirit) cannot, then, be separated in their reward, when they are united in their works."
This text graphically lets us reflect on the sacramental gestures Jesus performed in leading the deaf man so that his ears and heart and spirit could "BE OPENED".
In the Bible, we often read that "works of the flesh" are sins.
The problem is not with flesh itself.
The problem is when the spirit and the flesh do not work together. The flesh is meant to be subject to the spirit. When the two work according to their proper functions, the flesh is not a bad thing. It's when the spirit is subject to the flesh, and we allow ourselves to be led by our lower appetites, to the detriment of our higher ones, that the works of the flesh are sinful.