How Does Natural Law Work in and for Evangelism of the Lost?

Romans 1:18-21 read:

18 For the wrath of God is revealed from heaven against all ungodliness and unrighteousness of men, who hold the truth in unrighteousness; 19 Because that which may be known of God is manifest in them; for God hath shewed it unto them. 20 For the invisible things of him from the creation of the world are clearly seen, being understood by the things that are made, even his eternal power and Godhead; so that they are without excuse: 21 Because that, when they knew God, they glorified him not as God, neither were thankful; but became vain in their imaginations, and their foolish heart was darkened.

I'm assuming a lot of you readers know these verses.  According to them though, based on what people know, they will be judged rightly by God, because what they know means that they are without excuse.  At the same time, people are not going to experience the wrath of God's judgment because of ignoring information, but because of ignoring law.  When they knew God, they didn't glorify Him as God and were not thankful unto Him.  Glorifying God as God is represented by various prescriptions, which are laws.  This knowledge isn't a mere bunch of facts.  Bare acknowledgement of God's existence isn't sufficient to avoid the wrath of God.  The judgment and wrath of God is justice for disobeying natural law.

Natural law relates to the theological terminology, general revelation.  "General" is general in audience, that is, everyone knows it, so everyone is responsible for these laws.  Knowing God and glorifying Him as God in Romans 1 means knowing these laws to the extent that someone is responsible for obeying them.  They relate to the revelation of God, so according to His nature.  No one has an excuse for not knowing these.  They're natural to know.  All men are responsible for them.

In my assessment, the natural laws are those most denied, and against which men are most rebellious.  On the other hand, men like what they consider to be their natural rights, like what Thomas Jefferson's Declaration of Independence mentions at the beginning:

When in the Course of human events, it becomes necessary for one people to dissolve the political bands which have connected them with another, and to assume among the powers of the earth, the separate and equal station to which the Laws of Nature and of Nature's God entitle them, a decent respect to the opinions of mankind requires that they should declare the causes which impel them to the separation.

We hold these truths to be self-evident, that all men are created equal, that they are endowed by their Creator with certain unalienable Rights, that among these are Life, Liberty and the pursuit of Happiness.

He uses the language, "Laws of Nature and of Nature's God," "truths to be self-evident," and "endowed by their Creator."  Natural laws are self-evident truths.

Men know natural laws. They're natural to them, so to deny them, they are at their most rebellious.  The Apostle Paul talks about some of them later in chapter 1.  They rebel against God's natural order, because it clashes with what they want.  It's natural that the woman is the weaker vessel, and women very often don't want to hear that.  The natural order of two parents and children obeying their parents is repulsive to children.

When people think of the Declaration, they especially think, "all men are created equal."  They focus on the word, "equal."  Most often, however, I've noticed that they ignore the first four words, "all men are created."  It is self-evident that "all men are created." Equal, yes, but it is self-evident that man is created by God.  To Jefferson, creation of man carried with it more than sheer existence.  With God as Creator, He s also Lawgiver and then Judge.

I've found when evangelizing lost people that they will still act like they don't know certain things. Since Romans 1 says they really do know, I assume they do.  This is presuppositionalism.  I presuppose people know what is natural to know.  Many of those things people say they don't know, they rely on for enjoying their lives, which is why Jefferson uses "Life, Liberty, and Pursuit of Happiness."  People like those things and yet they act as though they've somehow received them by accident.  This is the part in Romans 1:19, "who hold the truth in unrighteousness."  As many of you know, it means they suppress the truth.  The way I put it is that the problem is not intellectual, but volitional.

Romans 1:18-22 assure what is already known by everyone.  I'm saying, you know that everyone knows what Romans 1:18-22 say because those verses say they do.  People can act like they don't know, but you know that they do, so that you don't believe that they don't know.  God says they do know, so they do know.

If someone is suppressing the truth, that means he knows and he is rebelling against what he knows.  In evangelism, you expose the lost on his rebellion.  How do you do that?

When I encounter someone who says he is a scientist, a professing atheist, too uncertain, or just not sure because he says he's not gotten enough proof, I rely on natural law.  I refer to a number of different examples.  "When you look out there at the vast and intricate world, does that look like it all came about by accident?"

I haven't found anyone who likes to be characterized as thinking or believing that everything came about by accident, but if this world isn't an accident, then it is design.  People know this is design.  Scripture says, according to the way I like to put it, that they don't want to have a boss.  The Designer would be their Boss.  They like having their own way, which you can read in the rest of Romans 1 and in 2 Peter.  2 Peter 3 says these scoffers are walking after their own lust.

I continue.  "Everything out there is so complex.  So many occurrences have to be going right at one time, that it is mathematically impossible to be an accident.  It looks like design.  Four or five hundred different circumstances need to be going right for us to even survive.  If just one of those hundreds does not go exactly right, we couldn't survive.  This can't be an accident.  The human body itself is so complicated, the human eye, speech, the operation of the brain, the circulatory system, our heart beat, so many that have to be functioning in just a certain way at one time.  And that's just to survive."

Romans 1:21 says, "Neither were thankful."  "So we breathe God's air, eat the food that comes from a seed growing from the ground, enjoy all of the good things all around on this earth, use all of that, and then just ignore Him."  This is when you can turn to scripture to point rebellion out.  "Romans 1 says that everyone already knows all this and rather than worship and serve the Creator, they serve the creature.  It describes this as not being thankful, being unwilling to give the credit to God, because that acknowledgement would carry with it responsibility.  Next chapter, Romans 2, says the goodness of God leads us to repentance."

The statement of what people know, natural law, aligns with what is written by God in men's hearts as a default position (Romans 2:15).  Pointing out natural law strikes a cord in men's hearts, their conscience then also bearing witness (v. 15).  They feel guilty because of their ungratefulness.

Then I may say, "What we see occurring out in the world also aligns with the Bible.  The history of the world reflects what we see there.  There is a God, we are here because of Him, He has put us here for a particular purpose, we are responsible to Him, and we are going to meet Him someday.  This is what the gospel is about.  God is just, but He also loves us, and the good news is that He wants us to save us.  However, we really do need to be saved."

Since the problem is not an intellectual one, the solution is supernatural.  The volition, the will of a person, must be dealt with scripture.  The Bible is powerful (Hebrews 4:12) and a spiritual weapon to pull down the strongholds in people's minds (2 Corinthians 10:4).

The approach I'm giving you is biblical.  It's what the Apostle Paul did in Acts 17.  It doesn't mean that it will result in your audience either listening or being converted, but it gives people an opportunity, which is what you want.  It might be too late for most.  You don't know.  More than ever, we're living in an age in which natural law is a necessity in an evangelism approach.