One of the best portrayals of what lies at the core of Christian faith is this amazing story of the Lost Son in Luke 15, which is an expression of what God did for us on the Cross. The open arms of the father in this parable are a picture of who God is, how God has acted toward sinful humanity—and also how we ought to act toward those who have sinned against us.
This parable has significant implications for how we relate to one another in situations of conflict, enmity, wrongdoing, or suffering. The basic challenge in all human conflict is the same one identified in the story of this prodigal: the relationship between justice and peace, liberation and reconciliation, law and grace. Do you call first for justice, then peace? First liberation, then reconciliation? Or is it the other way around?
In Jesus' parable we see that the primacy was given to grace, embrace, reconciliation. At the center of Christian faith lies this theology of embrace: The father will not give up his relationship with his lost son in spite of his son's wrongdoing. When that son returns, the father runs toward him without having heard a single word from that son. He shows his son grace and acceptance because the prodigal was and is and remained his son even through the wrongdoing.
That is what we see on the Cross. The significance of the Crucifixion is not only what God does for us; consistently throughout the New Testament the Crucifixion is portrayed as the pattern that we are to follow.