The existence of God and humanity’s inner sense of God
"For the wrath of God is revealed from heaven against all ungodliness and unrighteousness of men, who suppress the truth in unrighteousness, because that which is known about God is evident within them; for God made it evident to them" (Rom 1:18-19).
Every human being has an inner sense that there is a God. Everyone is accountable, whatever their background, however they may have been raised, and whatever they have been told. “They are without excuse.” No one can complain that there is insufficient evidence and that they had no way of knowing that God exists.
Every human being who has ever lived has known there is a God. But this is knowledge that some willfully reject because they are unwilling to submit to Him. The Bible describes those who say that God does not exist as fools (Ps 14:1).
This inner awareness gets stronger and clearer as we become Christians, but it is there in every person in a way that has to be purposely ignored or rejected by those who deny His existence.
(Spotlight 1, Lesson 1 in Doctrine 101: Learning about God)