Genesis 26:25 And he builded an altar there, and called upon the name of the LORD, and pitched his tent there: and there Isaac’s servants digged a well.
Isaac is in the land of the Canaanites! He is building an altar to God. The men know him and respect him. Isaac is friends with the king of the Philistines. They know him. They know about his God. They know about his worship and his altar.
They have seen God, His man, and His worship. They are without excuse.
I have paid more attention this time through in reading my Bible. I want to see if those who will later be destroyed by God had ample chance to know about Him and reject Him.
It appears that they did. Those chose their idols and false gods over the God of Israel!