(59) Not to fulfil the desires of the flesh (cf Gal 5:16).
This counsel of St. Benedict's is a quote from St. Paul's letter to the Galatians, "But I say, walk by the Spirit, and do not gratify the desires of the flesh," (Galatians 5:16). St. Paul saw the flesh and the Spirit at war with one another and one would suspect that so would St. Benedict. The flesh for Paul was an obstacle to being the person God had created us to be.
But less we project all of our own ideas about what the "flesh" means, let us look at what St. Paul means when he speaks about the "flesh": "Now the works of the flesh are plain: fornication, impurity, licentiousness, idolatry, sorcery, enmity, strife, jealousy, anger, selfishness, dissension, party spirit, envy, drunkenness, carousing, and the like. I warn you, as I warned you before, that those who do such things shall not inherit the kingdom of God," (Galatians 5:19-21). If one peruses the list one will find that the "desires" of the flesh are all the ways that our desires can go mad and lead to our own destruction.