Charles Ellicott Commentary Isaiah 58:4

"Behold, ye fast for strife and contention, and to smite with the fist of wickedness: ye fast not this day so as to make your voice to be heard on high." — Isaiah 58:4 (ASV)

Behold, ye fast for strife and debate. —The words possibly point to the psychological fact that an unspiritual fasting irritates the nerves and embitters the temper. Extremes meet, and the disputes of fasting controversialists are often as fierce as those of drunken disputants. (Compare to the conspiracy of Acts 23:21.)