“[…] The spirit searches into all things, even the deep things of God.”
~1 Corinthians 2:10

It is impossible to know God without the guidance of his holy spirit.
This is why many historians miss truths that are otherwise obvious to Bible readers who pray prior to studying. (2 Cor. 4:1-6)
The other side to this is people who say they believe but do not take the time to diligently compare Bible prophecies with their respective fulfillment.
This is why many people have heard of God’s kingdom but cannot explain its role in the course of human events. (Dan. 2:44; Matt. 6:9,10)
Or they believe God’s sacred secret continues to be a mystery. (Rom. 16:25,26; 1 Cor. 2:7)
Most people nowadays are familiar with God’s name being Jehovah or Yahweh, but remain reluctant to use it. (Ps. 83:18)
God has carefully set truths in his Word in such a way that only those having a humble attitude can understand them. (1 Cor. 1:19, 25; 2:14; 3:18-20)
May we never underestimate the value of God’s knowledge. (Prov. 2:1-11)