The Isavasyopanishad advises the combination of action with objective knowledge and not with Absolute knowledge. The Absolute is always opposed to objectiveness. Action and Absolute knowledge differ from one another in their causes, natures and results. Action is caused by the sense of imperfection. Its nature is distraction and its result is perishable. Knowledge is caused by perfection. Its nature is peace and its result is eternal. Hence action and knowledge are different from one another. It is not possible to say that action can be combined with knowledge in the beginning, though not is the end, because the moment there is the dawn of knowledge there is the cessation of action. It is not possible for fire to be hot and cold at the same time. Knowledge cannot co-exist with its opposite, viz., action that is characterised by motion. Knowledge is motionless. When the cause of action, viz., ignorance, is removed, all its effects also are removed.
Further, if the Upanishad had propounded the combination of action with Absolute knowledge, there would be no meaning in the aspirant's asking for a passage through the Sun after the attainment of Absolute knowledge. Absolute knowledge gives rise to immediate realisation or Sadyo-mukti. The fact that the prayer is for passing through a passage shows that the dying person has not yet attained Absolute knowledge. Hence the combination of action is only with relative knowledge, for, in Absolute knowledge there is no passing to any region, and there is no motion, whatever. Absoluteness means existence merely, and not changing or moving.