Jesus will not withdraw from you to save himself. By going to the cross he was bringing us into his light. When he says this is body and this is my blood it is not to hurt you but to give you the holy spirit so you are more ready to withstand the attack of the devil and not fear to stand in opposition to this evil age.

It’s not that God doesn’t know the thoughts and motivations of your heart but in asking us and these first disciples he is doing two things. First he is asking not for his own knowledge but for us to learn to repent. Second he is asking so that we might proclaim who he is and what he has done.