In the book of Genesis 4:14,the bible was talking about Cain, even though Cain sin against God,he still believe in the power of God,he still acknowledge God.
Going against the ordinances of God does not start today,it started from the days of Adam according to the book of Malachi 3:7.
God said we should return to him so that he will return to us.
The reason of those who don't believe in God is because they have turned away from God,they believe in their own hearts that there is no God,they don't want kindness from their fellow men,the give excuse to the evil they do,they have been separated from God because of their evil deeds,they believe the bible is a mere story and a fiction.
Evil people are increasing everyday and they don't feel guilty of their evil deeds,they believe there is pleasure in sin.
There is a God who created us,and he has given us the opportunity to know him and to turn away from our sin,so that we will be save and be with him in heaven.let us return to God so that it will be well with us.thank u.