Florentinus de Boeck (1826 - 1892), father of August de Boeck, was an amateur composer who succeeded his father-in-law as organist in Merchtem in 1858 (where his son August would succeed him after his death). De Boeck Sr. made a living as an agent for a financial institution and is said to have also owned a small brewery. If Florentinus de Boeck survives as a composer, it is as the author of that one Pie Jesu, which was sung in Merchtem for a long time and was also heard at the funeral of his son August de Boeck.