As a teenager I started to read books on Christian mission in my parents' home in Kockengen, a village near Utrecht, Netherlands. They were supporters of the Reformed mission among the Tor aja people in Sulawesi, Indonesia. While I was a student at the university, I received from my father a signed copy of the Reformed Mission League's volume Alle volken (All Nations) (The Hague: Van Keulen, 1963), which I still possess.
As a student in theology at Leiden University, I studied Christian missions, following the curriculum decided by my church, the Netherlands Reformed Church. The professor required extensive knowledge of only one book: Hendrik Kraemer 's Christian Message in a Non-Christian World (London: Edinburgh House Press, 1938). This volume, which Kraemer wrote in seven weeks, was the first missiological work I studied carefully; it became the book that most impacted my understanding of Christian mission. Before studying this classic work, I examined Der Islam (Basel: Basier Missionsbuchhandlung; Stuttgart: Evang. Missionsverlag, 1956), by Emanuel Kellerhals. He pointed to Kraemer as one of the three key figures for studying the history, doctrine, and nature of Islam from the standpoint of a Christian missionary.
During my stay in the mission house at Oegstgeest (1968-71), I combined the drafting of my Leiden University dissertation (on the rational views of Enlightenment philosophers on Jesus Christ) with preparatory studies for doing missionary work in Indonesia. The latter were focused upon the unity and variety of people groups in the Indonesian archipelago, their languages, history, and religions, with special reference to Protestant Christian missions and churches. I frequently talked with Bernard J. Boland, a former missionary who at the same time was completing his Ph.D. study on Islam in Indonesia, published as The Struggle of Islam in Modern Indonesia (The Hague: Martinus Nijhoff, 1971). Most of my teachers in the mission school, later known as the Hendrik Kraemer Institute and nowadays located in Utrecht, were former missionaries in Indonesia. Some of them wrote books in Indonesian, others in Dutch or English. The rectors at that time, for instance, published some stimulating studies. Evert Jansen Schoonhoven's inaugural address at Leiden University, which dealt thoughtfully with the tensions between mission and tolerance, was published as Zending en tolerantie (The Hague: Boekencentrum, 1962). His successor, Ido Enklaar, published De scheiding der sacramenten op het zendingsveld (The Separation of the Sacraments on the Mission Field) (Ph.D. diss, Amsterdam, Holland, 1947), in which he criticized the Dutch missions (and Indonesian churches) that did not allow all baptized members to immediately take part in the Eucharist.
During my stay in Indonesia (1971-80), I published a bibliography of religious studies and Christian theology in Malay and Indonesian since the seventeenth century. The second volume of this work contains one chapter on missiology and another on polemics and apologetics. In both chapters publications written by Indonesians alternate with translations of Western books. Reference is made to studies of two pupils of Johannes C. Hoekendijk, my predecessor at Utrecht University, who became the founding fathers of missiology as a theological discipline in Indonesia: the Indonesian theologian Johannes L. C. Abineno, who wrote Sekitar theologia praktika (Regarding Practical Theology) (Jakarta: BPK, 1969), with a large chapter on Christian missions, and the Dutch missionary Arie de Kuiper, who wrote Missiologia: Iltnu pekabaran Indjil (Missiology: The Science of Preaching the Gospel) (Jakarta: BPK, 1968). Their thoroughly grounded studies helped me to express my own thoughts in Indonesian.
In the same period, Asian theology outside the setting of Indonesia began to attract my attention. A seminar for Asian and Western teachers …