This doesn't mean (as many Atheists believe) that we are fearful to engage someone in an intelligent conversation addressing the intellect. Rather, I say it because the Bible uses the word "natural" or "carnal" to describe the mind of someone who doesn't know God. They can only think carnally, in a natural realm. The Scriptures go on to say that this "carnal" mind is in a state of continual hostility towards God.
This hostility can be seen in blasphemy (what atheists call "the Victimless crime"), mockery, anger, hatred, or denial of God’s existence. In most cases the hostility or mockery is directed at God's visible representatives.
If a Christian wants to try and reach an Atheist with the message of everlasting life and engages the carnal mind with subjects such as the existence of God, evolution, general apologetics, etc., more than likely he will find resistance, be mocked, or shown hostility.
To deal with this, the Bible tells us where we are to direct ourselves when speaking to the unsaved. It is to their conscience or what the Book of Romans says is the "work of the Law written on their hearts" (see Romans 2:15). This is what Jesus did in Mark 10:17, and the Apostle Paul did in Romans chapter 2.
If I address a sinner's conscience, he has no argument because it "bears witness" with the moral Law. Who of us can say that it's right to lie (not referring to "Grandma your hat looks nice," when you don't really believe that), or to steal (not meaning stealing a loaf of bread to feed your eight starving kids). It's the same with adultery and murder.
The conscience will always agree with the moral Law, unless it is "seared" and has lost its ability to do its divine duty. That is no doubt the case with some on this blog. The batteries have been removed from the smoke detector, and so they are given over to a "reprobate” mind (see Romans 1) and are without hope.
