Believers’ Baptism as the Biblical Occasion of Salvation John D. Castelein The yellowing card measures 6 inches by 4 inches. It is written in Flemish (what Belgium’s Dutch language is sometimes called). It says that John Castelein was immersed in Genk (Belgium) on December 29, 1957, by Dominee Don Castelein. One corner mentions Ephesians 4:5 (“one Lord, one faith, one baptism”); the other corner reads, “Abide in Me, and I in you” (John 15:4).