T. Austin-Sparks emphasizes the duality of Christ's work: Christ in heaven and Christ within believers. He explains that while Christ's completed work in heaven assures believers of their perfect salvation, the subjective work of Christ within them is essential for spiritual growth and maturity. Sparks warns against the dangers of overemphasizing either aspect, which can lead to spiritual shallowness, delayed maturity, and a lack of true transformation. He encourages believers to maintain a balance between the objective truth of their salvation and the subjective experience of Christ's life within them. Ultimately, understanding both aspects leads to a fuller realization of their identity in Christ and the hope of glory.