Be not afraid of their faces; their fierce looks, Eze_3:9, the indication of their enraged minds, Dan_3:19; neither when thou deliverest my message to them, nor when thou mayst be cited before them, Mat_10:18,19. This is God’s answer to Jeremiah’s fears in respect of the persons he was to deal with, as the other was in respect of his own consciousness of insufficiency; and he mentions their faces, because the majestic countenance of princes and magistrates is apt to strike a great awe and terror upon children.
I am with thee; I will not only send thee as other kings do their ambassadors, but I will go with thee. This God promises to Moses, Exo_3:12Deu_31:6,8.
To deliver thee: here God promises his protection for encouragement.