To be able to continuously keep the flesh (physical nature) under control, a person must live and walk in the Spirit (Galatians 5:16).
It is essential to understand that to succesfully walk in the spirit we must be able to carefully separate our human spirit from our soul and our physical body. This happens by realising that you were created as a spirit in the very image of God and the Holy Spirit indwells in your spirit (Genesis 1:26-27, 1 cor 3:16)
Taking the time to mediate and identify yourself as a spirit created in God’s image—both male and female—allows you to distinguish your true self from your soul and your physical body.
Just as you look into a physical mirror to see your body, the “mirror” that allows you to see your spirit is the Word of God (John 6:63).
Since the fall of man, the disobedience of Adam and Eve led to sin. This sin found a way to act through our human bodies, leading to what the Bible calls “the flesh” (Genesis 3:6, Romans 5:12).
Sin will always try to use the human flesh to show its true nature. These behaviours include: adultery, sexual immorality, uncleanness, indecency, worshipping false gods, witchcraft, hatred, arguing, jealousy, fits of anger, selfish ambition, causing divisions, following wrong teachings, envy, murder, drunkenness, wild parties, and other things like these (Galatians 5:19-21).