The scriptures are multi-faceted. Just because God decrees something does not mean that God actually desires it or that it is the best thing. For instance: divorce is permitted under the Mosaic Law even though God does not desire it.
Matthew 19:3-9 Some Pharisees came to him to test him. They asked, “
Is it lawful for a man to divorce his wife for any and every reason?”4 “Haven’t you read,” he replied, “that at the beginning the Creator ‘made them male and female,’a]">[
a] 5 and said, ‘For this reason a man will leave his father and mother and be united to his wife, and the two will become one flesh’b]">[
b]? 6 So they are no longer two, but one flesh.
Therefore what God has joined together, let no one separate.” 7 “Why then,” they asked, “did Moses command that a man give his wife a certificate of divorce and send her away?”8 Jesus replied, “
Moses permitted you to divorce your wives because your hearts were hard. But it was not this way from the beginning. 9 I tell you that anyone who divorces his wife, except for sexual immorality, and marries another woman commits adultery.”
Justice is good and holy, but it is not the best or most desirable outcome.
James 2:12-13 Speak and act as those who are going to be judged by the law that gives freedom, 13 because judgment without mercy will be shown to anyone who has not been merciful. Mercy triumphs over judgment.
Thus when interpreting scripture, the scope of that scripture is in fact the entirety of the scriptures. Scripture interprets scripture, as it were. What does God truly desire? What is the true intent of the law in question? It is not enough to look at a verse in isolation to come away with a proper understanding of what is being said.
With regards commandments calling for death for various sins, there is nothing wrong with these on their own. They teach that these are sins and not to do them. The wages of all sin is death in the end. However, that is also a very limited understanding of what is called for from us. For it is not God's desire that people be put to death, but that they repent of their sinful ways and be forgiven. It is God's desire that we do what is right and good rather than make sacrifices. It is God's desire that all be saved. And you would only be able to approach these commandments from this perspective if you took the time to study the whole of scripture and understand the overall will of God rather than picking out isolated texts.
The scriptures speaks in both ideals and reality. For while they show us the ideal, they also address the reality that people are sinful and don't live up to those ideals. Justice is good, mercy is better, and living righteously to begin with is the ideal.