Sin is the most unpopular subject in modern Christianity — not because people disagree that bad things exist, but because the biblical definition of sin is far more comprehensive than most people are comfortable with. It's not just the crimes. It's the attitudes behind the crimes. It's not just what you do — it's the condition of the heart that produces what you do. And until you understand sin biblically, you can't understand salvation biblically.

Last time we saw the authority Christ has placed in the hands of every believer. Now we turn to the problem that made that authority necessary: sin — what it is, where it came from, and what it costs.

1. LAW MEANS A RULE OF ACTION

Law is a rule of action established by a recognized authority to enforce justice and define what we owe to one another and to those in charge. Physical law governs the material universe—it keeps planets in orbit and seasons cycling according to God's design.

Moral law, on the other hand, is the rule of action for beings like us—free moral agents—guiding how we use our choices and creative abilities according to God's plan. Think of it like this: physical law is the rails a train runs on automatically, but moral law is the road map for someone who can choose which way to drive.

2. THE PURPOSE OF MORAL LAW

Moral law exists to reveal and declare the right way for free wills to act regarding the highest good of everyone and everything in the universe. It governs our acts and intentions in our relationship with God and all creation.

It speaks to our reason, showing us what we ought to choose, will, and intend.

3. THE IMMUTABILITY OF MORAL LAW

Moral law can never change. Its demand remains the same: that all free wills devote themselves to the same goal God pursues—the highest good of the universe and everything in it.

Even when free wills rebel, God's plan for creation's good doesn't budge. Because of this, the moral law stays constant forever.

4. THE OBLIGATION OF MORAL LAW

Because moral law exists for the good of all beings, it's naturally binding on everyone. Whatever works against the good of beings is obviously wrong and must be prohibited.

We, as free moral agents, must work together to bring about the greatest public good and stand against whatever brings misery and hardship to society. It's a mutual plan benefiting each person and the whole universe—and we're all obligated to keep it according to the light we've received.

5. THE REQUIREMENT OF MORAL GOVERNMENT

For moral law to work, there must be moral government to direct, guide, and control moral agents. Think of it like traffic laws: without enforcement—without penalties for running red lights and rewards for safe driving—roads would be chaos.

There must be a standard of living to which all must conform to be part of society, and there must be a way of dealing with rebels who disturb the peace. Law without penalties and rewards isn't really law at all—it's just advice people can take or leave without consequences.

Moral government is obligated to execute the moral law faithfully and completely.

6. REQUIREMENT OF A MORAL GOVERNOR

Since we need moral law and moral government, we also need a moral governor—someone whose will and decisions are considered infallible by everyone under that government. This governor must be authoritative, not merely advisory.

He must maintain the respect of his subjects through faithful, unselfish service. He must be able to execute penalties and distribute rewards. Naturally, whoever is best qualified to rule and secure the highest good of all should be the one to rule—it's both his right and his duty.

No one but God can meet these requirements. His natural attributes, His perfect moral character, His relationship to the universe as Creator, and His history of absolute justice qualify Him alone to be the Supreme Moral Governor. Since our good and His glory depend on our mutual commitment to the same goal, He is obligated to require us to be holy and dedicated to helping Him secure the highest good of all.

7. FREE MORAL AGENCY DEFINED

Free moral agency consists of three things: intellect, sensibility, and free will. These form the foundation of our moral obligation to moral government.

The intellect includes reason and self-determination. Sensibility includes self-consciousness, all sensation, desire, emotion, passion, and feeling. Free will is the power to choose concerning moral law—it's your ability to choose good or evil without being forced.

This capacity was originally created in humanity, and we'll have it for all eternity.

8. THE BASIS OF RIGHT CHOICE

Our moral obligation to always act for the best good of all is the foundation of right moral action. Nothing happens in life except what someone chooses.

It's absolutely critical that we make right choices that bring about the greatest public and private good. This obligation extends to the deepest intentions of our will. We're obligated to choose holiness as the path to the greatest good and happiness.