In his early life, he taught rhetoric in his native town, which may have been Cirta in Numidia, where an inscription mentions a certain "L. Caecilius Firmianus".
Pada usia muda, ia mengajar retorik di kota asalnya, yang kemungkinan adalah Cirta di Numidia, di mana ada suatu inskripsi yang menyebutkan nama "L. Caecilius Firmianus".