Ziegenbalg regularly invited Tamil guests and visitors to his home for discussions on diverse themes ranging from religious faith to social customs to agriculture. Their conversations expressed their memories and perceptions of histories, socio-cultural habits and the Tamil language. Sixthly, he entertained letter correspondence with learned Tamil scholars living not only in the Kingdom of Tanjore, but also in distant places such as Tiruverriyur (Tiruvottriyur) in Chennai. Ninety-nine such letters are available in their German version. They clearly show Ziegenbalg’s consistent efforts to understand the roots and meanings of Tamil thoughts and customs. He translated parts of the Holy Bible and other Lutheran devotional literature (e.g. catechism, systematic theology, and the like) into Tamil. Ziegenbalg produced treatises on the Tamil and their socio-cultural life. For example, in 1708 he translated three minor works on morality, namely Koṉṟai Vēntaṉ, Ulaka Niti and Nitivenpa from Tamil into German so that his readers would appreciate the civility of Tamil public behaviour. In 1711, he prepared a monograph on Tamil Society (literally: Malabarisches Heidenthum, ‘Malabarian Heathenism’); and two years later in 1713, he compiled his well-known work entitled The Genealogy of the Malabarian Gods. In these works, he included Tamil quotes from various writings. In 1712, Ziegenbalg installed the first mechanised printing press in Tranquebar and began printing small Tamil works such as Nirupam (open ‘letter’) in 1712), Annanam evvalavu aruvarukkattakkatu (‘how detestable spiritual ignorance is’ in 1713) and Aintu Veta Puttakam (the ‘Five Vedas’, i.e. the four Gospels and the Acts of the Apostles from the New Testament in 1714). All these admirable activities and works enabled Ziegenbalg to indeed acquire a deep knowledge of the Tamil language. At the same time, it is doubtful whether this knowledge was sufficient to compile a grammar within four months. Ziegenbalg did not mention the sources for his grammar. One of the most decisive sources was definitely a Portuguese-Tamil grammar, which he had received from the Governor of Tranquebar. My research has demonstrated that this grammar must have been Balthazar da Costa’s Arte Tamulica and identified several resemblances between them. As mentioned below, Ziegenbalg had even translated certain parts of the Arte Tamulica (e.g. the entire chapter on Verbs) from Portuguese into Latin. This was probably the main reason that he could compile his grammar within four months!....