Denis was deeply religious and sought to return to prominence the subjects offered by his Christian faith. He explored ways to give these subjects a modern context, and had been greatly influenced by the stylistic headway shaped by Paul Gauguin. Denis was attracted by the decorative possibilities of religious subjects. In 1919, along with fellow artist Georges-Olivier Desvallières, he established the Ateliers de’Art Sacré which was committed to teaching young artists the various approaches and techniques suitable for modern religious decoration.