Malbim: Man's physical substance is destined to decay in the grave, and worms will consume it. The primary man is his spiritual Nefesh; his physicality is a garment in which it is clothed for a limited time. Afterwards, the earth returns to the ground. Can a person change the general conduct due to this garment that will decay?! Still, it is not injustice [that one suffer due to his Mazal]. In the future, a Tzadik will be paid for what he suffered, and a Rasha will be punished for the good that he received without Mishpat. This will be in the eternal world - the stars and Ma'arachah do not rule there! Bildad said like this in his first answer.