With the 1983 Codex Iuris Canonici, the concept of church office has changed, in that laypeople can now also be holders of certain church offices in the full legal sense, and canonical office law is applicable to them. Since then, church law recognizes the case where laypeople are appointed through a sovereign mission to professionally exercise a service in the church, thereby acquiring a legal status that goes beyond the basic position of a believer. The work attempts to capture the layperson as a professional holder of a church office from a canon law perspective and to illustrate the consequences that arise for both the employee and the ecclesiastical employer. The result shows that ecclesiastical employment relationships of laypeople cannot be treated solely according to the provisions of secular labor law by the church.