Albert Barnes Commentary Ecclesiastes 4:5

"The fool foldeth his hands together, and eateth his own flesh." — Ecclesiastes 4:5 (ASV)

Folds his hands - The envious man is here exhibited in the attitude of the sluggard (marginal references).

Eats his own flesh - that is, “Destroys himself:” compare a similar expression in Isaiah 49:26; Psalms 27:2; Micah 3:3.