I will not go up in the midst of thee by my own special and gracious presence, as hitherto I have done, but I will depart from thee. In pursuance hereof God removes his tabernacle without the camp, Exo_33:7. I will only make good my promise to thy fathers, and send an angel to accomplish it, but I will show no peculiar and further kindness to thee.
Lest I consume thee in the way; lest thy sins should be aggravated by my presence and favour, and thereby I should be provoked utterly to destroy thee. So he shows that their perverseness makes this severity necessary for them, and that God even in his judgment remembers mercy to them.