The Lord Jesus Christ is the only one who can make us right with God and in order for this to happen two problems must be overcome, our sin and God's wrath. This means that if we are to be saved from both, salvation must be accomplished through judgement. Christ is our substitute, but too often the images we have of substitutes (from team games or films, which some use to illustrate what happened on the cross of Christ) often simplify the act of substitution into error. These next four questions in the Heidelberg Catechism address the importance of Christ as our substitute. "Why must he be truly human and truly righteous?", "Why must he be truly God?", "And who is the mediator - true God and at the same time truly human and truly righteous?" and "How do you come to know this?"