“The special work of the Spirit is to apply the benefits of Christ’s mediation to the elect. There is a strict correspondence between Christ’s work and the Spirit’s work. For this reason, regeneration must never be considered apart from Christ; positively stated, regeneration must always be understood in relation to union with Christ… The risen Savior first apprehends the elect and makes them alive by His Spirit operating as the Spirit of Christ, so they can receive from Christ all the benefits of the work He accomplished on their behalf, as their mediator. Faith is only possible because Christ, through the Spirit, has joined Himself to the sinner. In response, the sinner exercises faith toward Christ, as an effect of regeneration. With the union complete, the sinner receives from Christ everything that Christ merited, including justification, adoption, and sanctification.” (Joel Beeke)
For more on this subject, please visit the Systematic Theology page.