Complex sentence: The school is named after Guido de Brès, a French Reformer who died as a martyr in 1567, and who wrote the Belgic Confession, one of the Three Forms of Unity for the Reformed churches.
Split into simpler sentences: The school is named after Guido de Brès, a French Reformer who died as a martyr to the faith in 1567. He is the author of the Belgic Confession, one of the Three Forms of Unity for the Reformed churches.