Do not think that I came to destroy the Law or the Prophets. I did not come to destroy but to fulfill. He was perfect. All the threatenings of the Old and New Testaments are threatenings either of the law or of the gospel. Every prophecy of Scripture is a declaration of things obscure and future and is connected with either law or gospel.
Every promise is a promise related to either the law or the gospel, or both.
Every good admonition, reproof, or exhortation is with reference to the law or the gospel, or both. Thus the law and the gospel are the center, the sum, and the substance of the whole Bible. The closer we get to a clear view of the difference between the law and the gospel, and the connection between them as they serve to establish each other, the more we will understand the Holy Scriptures and thus the will and mind of God, and the more useful we will be in His service. God's law comes from His nature. The nature of God determines what is right, and the will of God imposes that standard upon all His creatures as a moral obligation.