Exodus 33 Moses pleads with God to continue on with Israel: 'For how shall it be known that I have found favor in your sight, I and your people? Is it not in your going with us, so that we are distinct, I and your people, from every other people on the face of the earth?' The lesson from this chapter is that, if you can't have the blessing and presence of God in doing something, then it isn't worth doing at all; 'If your presence will not go with me, do not bring us up from here.'
Exodus 34 If God's relationship with Israel is like a marriage, then God is like the husband of a cheating wife. Two chapters ago Israel made an idol and worshiped (in effect) another god. In the last chapter Moses plays the mediator. Finally, in this chapter, God looks with His eyes upon unfaithful Israel and renews His wedding vows to her: 'I am making a covenant. Before you I will do marvels, such as have not been created in all the earth or in any nation. And all the people among whom you are shall see the work of the Yahweh, for it is an awesome thing that I will do with you... I will drive out before you the nations.' It's kind of sweet, in an 'I am going to help you wipe out a nation,' sort of way.
Exodus 35 With the covenant renewed and the 'marriage' re-made, work on the Tabernacle begins. Israel comes on her part and makes amends by giving generously to the building project; every man and woman contributes something to the Tabernacle construction project. This is God's sign that He will be with His people, in the midst of them, as their faithful God and protector. The Tabernacle (and keep in mind what just happened a couple of chapters ago) is God's sign that He will be with this nation that isn't yet a true geographic nation.