關於政教分離的原則，2,000年前耶穌基督曾經親自指示「凱撒的物當歸給凱撒，上帝的的物當歸給上帝」，與此同時，耶穌基督指示門徒恪守宣教的大使命「去使萬民做我的門徒」。這兩個看似無關的吩咐，卻在某一群特別的人身上，成為兩個天天要面對的選擇，這群人就是在公部門任職的基督徒。政教分立和職場宣教有無衝突？大部分的基督徒公務員如何在職場安身立命？如何在政府機關進行職場宣教？所面臨的困難是什麼？不同教派的基督徒是否有不同的差異性？非教徒的長官、同仁、屬下，怎麼看待這些基督徒公務員呢？本研究作者以一個基督徒公務員的身分，長期參與觀察公部門團契，進行探索性的研究。

Regarding the principle of separation of church and state, Jesus Christ, more than 2,000 years ago, personally directed others: “Render therefore unto Caesar the things which are Caesar’s, and unto God the things that are God’s.” At the same time, Jesus Christ instructed his disciples to hold to the great calling of proselytization: “Go, therefore, and make disciples of all the nations.” These two seemingly unrelated instructions have become two choices that a particular group of people faces every day. This group is comprised of Christians serving in the public sector. Is there any conflict between the principle of separation of church and state and workplace proselytization? How do most Christian civil servants come to terms with this issue and continue on in the workplace? How do they carry out workplace proselytization in government agencies? What difficulties do they face? Are Christians from varying denominations different in how they approach these issues? How do non-Christian senior officials, colleagues, and subordinates view these Christian civil servants? The author of this study, as a Christian civil servant, has long been involved in observing Christian fellowships in the public sector and conducting this exploratory research.