We can distinguish [the] two aspects of our union with Christ this way: Our legal union with Christ entitles us to all that Christ did for us as He acted in our place, as our substitute. Our vital union with Christ is the means by which He works in us by His Holy Spirit. The legal union refers to His objective work outside of us that is credited to us through faith. The vital union refers to His subjective work in us, which is also realized through faith as we rely on His Spirit to work in and through us. Though our union with Christ has two aspects, it is one union. We cannot have legal union without also having vital union. If through faith we lay hold of what Christ did for us, we will also begin to experience His workings in us.