The Trinity in the Gospel

The gospel is the good news of God the Father planning our salvation, God the Son, the Mediator, achieving it for us, and God the Holy Spirit applying it to us as the gracious, willing guest who indwells us. Deny the Trinity, and, consequently the incarnation and the personal ministry of the Holy Spirit…and the gospel…simply falls to pieces.
J.I. Packer
Praying: Finding Our Way from Duty to Delight

p. 24