Friday fasting is a remembrance—and to a certain extent, identification—with the cruxifiction. Mild discomfort to commemorate a much stronger act of self-denial

Friday fasting is a remembrance—and to a certain extent, identification—with the cruxifiction. Mild discomfort to commemorate a much stronger act of self-denial. It's documented as early as the 3rd century by Clement of Alexandria (Stromata VI.75) but as you point out it's a logical extension of a practice that was integrat to the Jewish tradition.