Romans 1:20-21

God's Wrath on Unrighteousness

²⁰ For his invisible attributes, namely, his eternal power and divine nature, _n have been clearly perceived, ever since the creation of the world, in the things that have been made. So they are without excuse. ²¹ For although they knew God, they did not honor him as God or give thanks to him, but they _o became futile in their thinking, and their foolish hearts were darkened.

1. Cross References
   Psalms 19:1 - 6
   The heavens declare the glory of God, and the sky above proclaims his handiwork.
   Jeremiah 5:21 - 22
   Hear this, O foolish and senseless people, who have eyes, but see not, who have ears, but hear not.
   
2. Cross References
   2 Kings 17:15
   They despised his statutes and his covenant that he made with their fathers and the warnings that he gave them. They went after false idols and became false, and they followed the nations that were around them, concerning whom the Lord had commanded them that they should not do like them.
   Jeremiah 2:5
   Thus says the Lord : "What wrong did your fathers find in me that they went far from me, and went after worthlessness, and became worthless?
   Ephesians 4:17 - 18
   Now this I say and testify in the Lord, that you must no longer walk as the Gentiles do, in the futility of their minds.