Law in Amos 2:4 refers to instruction, not legislation and its enforcement. From a verb that means "to throw," its root describes casting lots or throwing dice. When lots or dice were cast, God revealed His will in the way they landed (Proverbs 16:33; see Leviticus 16:8-10; Acts 1:26). At times lots were used in making judgments in criminal cases in which God's will needed to be ascertained (Joshua 7:13-25). Thus, by setting a legal precedent, the casting of lots served to give instruction in other cases in which the same basic principles of behavior were involved. God's will—His law—was taught to His people through the casting of lots.
This instruction process implies a teacher-student relationship. When the Israelites rejected God's instruction contained in His law, they rejected the Instructor as well. Their relationship with Him quickly deteriorated.
Commandment means "to engrave or cut into stone," suggesting its permanence and immutability in contrast to temporary and changeable lies. The law comes from an unchangeable, righteous, and pure God in contrast to fickle and iniquitous men.
Judah's despising of God's law and revelation of Himself was internal—from the heart (Psalm 78:37; 81:11-12; Jeremiah 5:23). The personal and social failures Amos records are evidence that the people had rejected the truth. So it is with us: God wants to change our hearts so He can change our actions and turn around our lives.
In every area of life, Israel perverted the truth of God to accommodate the ideas of men. In the final tally, they loved lies rather than the revelation of God (II Thessalonians 2:11-12). Thus Amos says that God's people despised His law. They made the mistake of devaluing their calling and considered it common. Believing they were God's elect, they thought they were irrevocably saved. With this attitude it was only a matter of time before spiritual and moral complacency set in. As the church of God, we cannot allow ourselves to slip into this attitude because we, too, would fall into immorality.
If that occurs, God must pass judgment because His justice is the same for everybody (Colossians 3:25; I Peter 1:17). God's laws govern the people on the outside as well as the people on the inside. No matter what makes Israel or the church distinctly different, His judgment is always righteous. When God could not change Israel's immorality through His prophets, He had to punish them. So will He punish an apostate church.
It is easy to see why this book is written to the end-time church. The people of America and the British Commonwealth are already in the moral and spiritual condition of the people of Israel and Judah in the time of Amos. Members of God's church come out of such a world. Just as Israel's privileged position became a curse, so will it be for the Christian who ultimately rejects his calling (Hebrews 6:4).