T. Austin-Sparks emphasizes the significance of the Holy Spirit's advent, marking a transformative shift in God's economy and the believer's relationship with Him. He explains that the Holy Spirit's role is to actualize the work of Christ in believers, making the realities of the Incarnation, earthly life, Cross, Resurrection, and Ascension manifest in their lives. Sparks highlights that the Holy Spirit is committed to glorifying Jesus and enabling believers to live in the newness of life, free from the old man. He urges Christians to recognize the importance of the Holy Spirit's work in their lives and to live in accordance with the resurrection life that He brings. Ultimately, the sermon calls for believers to embrace their identity in Christ and the transformative power of the Holy Spirit.