Michael Parsons, "'In Christ' in Paul," Vox Evangelica 18 (1988): 25-44.
Paul uses the term "in Christ" 216 times in his writings, but what did he mean by it? Michael Parson's concludes:
We have seen, then, that the ‘in Christ’ formula is important in the thought of the apostle Paul. It primarily designates a close and indissoluble relationship with the Lord, but more than that it speaks of solidarity with Christ in his death and resurrection as the representative head of his people, the church. However, in its implication the term underlies much of the apostle’s explanation of the believer’s awareness of the sanctifying work of Christ’s Spirit conforming him to the image of the Lord to whom he belongs and in the manifestation of this relationship in the life and communion of the body of Christ, the church. We have also seen, in passing, the importance of this teaching as it relates to Paul’s ethical thinking and exhortation. Lives in the present are to evidence the believer’s characteristic union with Christ in godliness and in obedience to him within the context of his church and by the power of his Spirit.