Jn 17:3, 2 Cor 4:6
In the Old Testament, God said that the people of Israel were destroyed because they did not know God. (Ho 4:6)
Ho 4:6 My people are destroyed for lack of knowledge: because thou hast rejected knowledge, I will also reject thee, that thou shalt be no priest to me: seeing thou hast forgotten the law of thy God, I will also forget thy children.
To know God and Jesus Christ whom God has sent is eternal life. (John 17:3)
John 17:3 And this is life eternal, that they might know thee the only true God, and Jesus Christ, whom thou hast sent.
Jesus Christ is the knowledge of God. (2 Corinthians 4:6)
2 Corinthians 4:6 For God, who commanded the light to shine out of darkness, hath shined in our hearts, to give the light of the knowledge of the glory of God in the face of Jesus Christ.