Then there is no wonder why Agus Suntoyo, in the book preface, mentioned that Wali Songo was an essential stakeholder in the spread of Islam in Java and Nusantara in the 15th until the half of the 16th century. But why is that?
Due to that statement, the theory that Islam was brought to Nusantara by Muslim traders is indisputable. However, it’s a fact that Nusantara inhabitants did not necessarily observe the arrival of those traders in the 6th century until the arrival of the Islam propagator on Java.
Hence, the opinion that Islam successfully spread is given credit to Gujarat traders is not valid. The successful spread is precisely due to the dakwah touch that Kanjeng Sunan used by arranging local culture and Islam values to get along together beautifully.
Kanjeng Sunan Bonang as an example. In doing dakwah, Radeng Makhdum Ibrahim is well-known for his competence in using art and culture devices to attract the sympathy of Javanese people. One of them was the Java music instrument that so-called Bonang. Bonang itself is a round-shaped music device made of brass with a slight bulge in its middle, pretty similar to a small Gong. Back in the era, this music device was used as a Gamelan accompaniment instrument in the wayang (traditional Javanese puppet show). Village officials also used it to gather citizens to make a wara-war, an announcement, from their government. (Page 238-239).
According to the writer, it is an ahistorical move, if it is not appropriate to say naïve when some historians and intellectuals gathered and discussed Islam of Indonesia without mentioning Wali Songo in their discussion with the consideration of different understanding and thought. This ahistorical and naïve fact is a crystal discovery you could found by reading Ensiklopedia Islam (Islam Encyclopedia) published by Ikhtiar Baru Van Hoeve.