Romans 1:19-21
19 Because that which may be known of God is manifest in them; for God hath shewed itunto 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.
We all agree that God exist. We can see it when we stop and look at nature or hear a newborn baby cry. There are many ways that people see the work of God. The sad thing is many believe he does not exist. They believe that over time we evolved and created the theory of a higher power. A few years ago I was visiting a church and had the honor to hear a man speak of how he used to be an atheist. It was that night that I learned these people who have given into their imagination can turn to God. So, when you feel that these people are beyond saving, stop and know that God can still touch the heart of a sinner. He can open their eyes to his existence. They will see his work in everything just like the rest of us.