Job 21:21 - Matthew Poole's English Annotations on the Holy Bible

What pleasure hath he in his house after him? or, for what desire, or care, or study hath he for or concerning (as beth is oft used) his house, i.e. his children? When he is dead and gone, he cares not what becomes of his children, as irreligion commonly makes men unnatural; he is not concerned nor affected with their felicity or misery. See Job 14:21. And therefore God doth punish both him and his children whilst he lives, Job 21:19,20. Or thus, What delight can he take in the thoughts of the glory and happiness of his posterity, when he finds that he is dying a violent and untimely death? So this is a further proof that this man is neither happy in himself, nor with reference to his posterity. When the number of his months is cut off in the midst; when that number of months, which by his constitution and the course of nature he might have lived, is diminished and cut off by the hand of violence.