We in the flesh are hindered in such a way that with our senses we cannot perceive eternity. The God who took flesh in the form of Jesus in order to be like us in all things chose to forgo some knowledge in agreement that such temporarily 'forgetting' was part of the perfection of the plan of God. As God shielded Moses when God passed by, Moses was denied a knowledge of God because his flesh could not look upon the face of God and live. So to Jesus while incarnate in the flesh would suffer a 'shielding', or a lack of knowledge of some things that He would have had access to prior to the incarnation and would again gain access at the exact moment of His last heart beat. This 'forgetting' of certain things for a time was part of God's participation in our humanity and the perfection of His passion on the Cross. The God who knows all could by His own will decide to forgo knowledge in order that an infinite benefit could be given to us by His Passion.