Knowledge of God is not head knowledge. Many know about Him, but they have no intimate communion. John 17:3 says, “And this is life eternal, that they may know You, the only true God, and Jesus Christ whom You have sent.”
Ephesians 3:19 in the Amplified explains intimate communion really well. It says, “(That you may really come) to know (practically, through experience for yourselves) the love of Christ, which far surpasses mere knowledge (without experience); that you may be filled (through all your being) unto all the fullness of God (may have the richest measure of the divine Presence, and become a body wholly filled and flooded with God Himself)!”
2 Peter 1:4 says that we enter into His very nature in our communion. Read this carefully. “By which have been given to us exceedingly great and precious promises, that through these you may be partakers of the divine nature…”