I'm sure you have heard about the atheist who was complaining to the Christian because there was no holidy for him. After all, he said, Christians have many holidays they celebrate.....i.e Christmas, Easter and such.
The Christian replied; 'but there is a holiday for you, April fools day.' Of course the atheist didn't understand that the Christian views all of life and those in it through the lense of the Word of God. So he had to explain that April Fools Day was his holiday because the scripture tells us so.
Psalm 14:1 "The fool hath said in his heart, there is no God"