When we look at the Israelite or Hebrew understanding of sacrifice in the lineage of the prophets, we see something radically different than that pagan model of God needing a sacrifice to forgive sins.  

God, in the Bible, is not bound by sacrifices.  God binds himself to a covenant with Israel.  N. T. Wright will point out that Israel wasn't going to keep that covenant because they were, as we are, human beings, but that does not dissuade God from going ahead and making a covenant with and remaking it, and remaking it . . . .and you get the point.  God loves the people, in fact the cosmos in John's language, so much that God is willing to come back time and time again to stay faithful to his promises in covenant with Abraham and his descendants.  

There is this consistent picture throughout the Bible of God's desire to walk with human beings in the intimacy of the Garden of Eden.  It is a heartbreaking desire that seems to constantly lead to despair and frustration for God.  

We have this Roman god in our heads that is beyond the reach of all emotions and perfect, immutable, and orderly.  YHWH is not that.  Throughout the Bible, God is a God who loves and loves passionately, to our scandal at times.  How can any respectable God act this way?  we think as we read about the tantrum of the flood or the rage of Amos.  We want a mature God.