Watchman Nee emphasizes that true deliverance from the flesh comes through the cross of Christ. He explains that while regeneration occurs through belief in Jesus' substitutional death, believers must also experience co-crucifixion with Christ to overcome the flesh's desires. Nee highlights that the flesh cannot be educated or cleansed but must be crucified, allowing believers to walk in the Spirit. He encourages those new in faith to understand the significance of the cross and the necessity of dying to the flesh to live victoriously. Ultimately, the path to freedom from the flesh is through identifying with Christ's death and resurrection.