Jessie Penn-Lewis discusses the concept of the 'carnal Christian,' emphasizing that many believers, though regenerated, remain dominated by the flesh and its desires, which prevents them from fully experiencing spiritual maturity. She explains that there are three types of Christians: the spiritual, the soulish, and the carnal, with the latter being characterized by jealousy and strife. Penn-Lewis highlights the importance of understanding the significance of the Cross for deliverance from the flesh, urging believers to reckon themselves dead to sin and to walk in the Spirit. She stresses that spiritual growth should not be stagnant, and that believers must actively seek to live according to the Spirit to overcome the carnal nature. Ultimately, she calls for a deeper comprehension of the Cross to achieve true freedom and spiritual maturity.