Jamieson, Fausset & Brown

Yet--rather, "Truly," or, But affliction does not come from chance, but is the appointment of God for sin; that is, the original birth-sin of man. Eliphaz passes from the particular sin and consequent suffering of Job to the universal sin and suffering of mankind. Troubles spring from man's common sin by as necessary a law of natural consequences as sparks (Hebrew, "sons of coal") fly upward. Troubles are many and fiery, as sparks (Pe1 4:12; Isa 43:2). UMBREIT for "sparks" has "birds of prey;" literally, "sons of lightning," not so well.