Explanation:

The Human Incarnation is always in the absolute plane and the relative plane never exists for Him because the illusion causing the existence of the relative plane is never for God. Hence, there is no question of the existence of the relative plane in the view of God at any time. Only we, the ordinary souls, are affected by the illusion and experience the existence of the relative plane. Since we can only imagine about the absolute plane and can never practically experience it in reality, we will not believe in the existence of the absolute plane even in the view of the Human Incarnation. Since, our practical experience is always confined to the relative plane, we always try to imagine the relative plane even for the Human Incarnation. Hence, the basic reason for us to not believe in the existence of the absolute plane for the Human Incarnation, is our lack of practical experience of the absolute plane at any time.