Divine Hiddenness - see the great video linked at the bottom of this post, as Dr. Gavin Ortlund speaks about this important topic!
There are many with unbelief in the God of the Bible that are SINCERE, as they have doubts and questions about His existence that they've not yet personally reconciled. Some of these sincere doubters look at a troubled, violent world and cannot see how a loving God would allow so many victims and suffering. In fact, even with Believers, especially whenever a tragedy hits close to home, we wonder about this as well - we may get angry, confused, but we've also learned to trust God, no matter what. Because we know God doesn't cause the evil that is in this world - people do. However, despite the immense difficulties and evil often found across this world, God has important purposes for allowing it (but ONLY for a period) - even if we often don't understand difficult aspects of it - because this world (as it is NOW) was never meant to last forever, as the Bible tells us of a new Heaven and restored earth to come.
So, for those sincere, who truly want to know the truth about God, He WILL reveal Himself to them, in His ways and timing. But then they STILL must commit themselves to Him, through faith in Jesus,to be saved - because mere belief does NOT save. Bit committing / submitting oneself to Jesus as their Savior DOES save!
Those who want to know the truth about God SEEK Him! And those who never do - WON'T! WHY - because they don't desire to find God, as the only god they desire are themselves, only wanting to make their own rules for living their lives however they may desire.
"I love those who love me, and those who seek me diligently find me." (Proverbs 8:17)
7 “Ask, and it will be given to you; seek, and you will find; knock, and it will be opened to you. 8 For everyone who asks receives, and the one who seeks finds, and to the one who knocks it will be opened." (Matthew 7: 7-8)
But there are also many more INSINCERE unbelievers that claim to see no reason to believe or commit to God / Christ because they insist there is no evidence of His existence and see it as absurd that He would remain so HIDDEN to them, if He truly existed. And for many such unbelievers, God's hiddenness has not to do with God, but with THEMSELVES! Because people avoiding, running from, or that are determined to continue resisting Him or refusing to seriously investigate any light or evidence for His existence are not seeking the truths that they COULD know, but don't know / don't WANT to know, as they refuse to accept, see or hear them. Or these unbelievers often feel certain that if God actually existed, He would make that clear by doing X, Y or Z miraculous things, typically, in ways which THEY would have done it. But if you talk to most Christians, they'll tell you of a point in their lives in which they just didn't believe much of anything about Christianity or the Lord, but that eventually their eyes began to open, to the point that His presence became clear to them. And then they eventually began to realize the countless amazing evidences about Himself He has given us all. These are people God revealed Himself to because they didn't permanently resist or close off their hearts and minds to Him. God simply is not going to force people to believe what they absolutely refuse to!
God also will not reveal Himself other than as He actually IS / His nature, attributes, desires for us, etc. Typically, unbelievers that resist God do so because THEY want to continue being their OWN boss (own god!), living as they like - no matter how sinfully (which they are often blind to), as they are unwilling to and don't desire to change their sinful ways. So, similarly, people insist upon building and accepting false constructs and beliefs, per whatever false religion or gods (or NO God / gods - excepting themselves) they desire to serve, in place of the True God of the Bible. Or, unbelievers make up unBiblical caricatures of the God of the Bible, and use them to convince themselves He doesn't exist (see this book: https://www.amazon.com/God-Moral-Monste ... 001&sr=8-1). And so, such people are ALSO resisting God / Christ by denying Him per whatever it is that they'd rather believe in, instead. And thus, God will remain hidden to them, until / unless they want to know the truth, again, as they have presently closed off their hearts and minds to the Lord. So, God will not FORCE anyone to know the truth about Himself - even though He wants them to know it. God wants us to FREELY love Him, un-coerced - as "forced love" is no love at all!
God wants ALL to come to knowledge of Him, to love Him. And He's made that very easy - for those who care about the truths surrounding God. All one needs is an open mind and heart, with a desire to know the truth about God. He's left massive evidences to the world, if they so choose to investigate. Just remember, God reveals Himself on HIS terms and timeline - and He knows the best ways to do that. Don't confuse that with an expectation that God reveals Himself as YOU think He should. Do a search on this site - you'll find plenty of understandings!
1 Timothy 2:3-4: This is good, and it is pleasing in the sight of God our Savior, 4 who desires all people to be saved and to come to the knowledge of the truth.
Lastly, if you TRULY desire to know of God, His existence, love, mercy, and promises for an eternity in bliss with Him - then sincerely ASK Him to reveal Himself to you, and He WILL, as He WANTS to. As if you truly want to know the truth about God, why would you not put Him to a simple test, in a quiet place, just you and God - pray something like: "God, I don't know if you even exist, and I have great doubt that you do not. But if you do, please show me clearly and make me understand the truth about You, and then give me the courage to ask you to save me. I want what the Bible says you offer EVERYONE, no matter the level of their sin and bad deeds - love, peace, guidance - and then eternity with you, in beauty and peace FOREVER. Amen!" If you are serious and sincere in such a prayer, the Lord WILL honor you!
Philip
“Ask, and it will be given to you; seek, and you will find; knock, and it will be opened to you. For everyone who asks receives, and the one who seeks finds, and to the one who knocks it will be opened." (Matthew 7:7-8)
Here, Dr. Gavin Ortlund expounds on this fascinating topic, the "Divine Hiddenness" of God:https://www.youtube.com/watch?v=8ynLwvSAQL0&t=26s