Have you ever been called a “know-it-all”? If so, it’s usually not a compliment. When someone calls you a “know-it-all,” they are sarcastically saying, “You don’t know as much as you think you do and I hope soon realize how little you actually know!” Ouch.

Does anyone really know it all? Yes, in fact there is One: God. God knows it all. His knowledge is instantaneous, total, and completely retentive. God knows what He knows without any kind of research, education, or strenuous study. He never had to go to school, take a test, or be informed about anything. You will never surprise Him with some new fact or beat Him at Trivia Pursuit. You can never tell God something He doesn’t already know; He knows it all. He knows when a sparrow dies, and He knows the number of the hairs on your head (Matthew 10:29–30). Even the number of hairs I am losing by the minute! In short, He is omniscient. His knowledge is eternal and infinite.

“Oh, the depth of the riches and wisdom and knowledge of God! How unsearchable are his judgments and how inscrutable his ways! “For who has known the mind of the Lord, or who has been his counselor?” “Or who has given a gift to him that he might be repaid?” For from him and through him and to him are all things. To him be glory forever. Amen.” (Romans 11:33-36′ cf. Psalm 139:17-18)

He knows you, even better than you know yourself.

David is king over all of Israel. Every person in his kingdom knows him as king. Although he is king, he doesn’t know everyone in his kingdom personally. However, He does know and honor the One who does know all and He knows David. He is God and He is King of kings.

In Psalm 139, David composes a song that grapples with God’s omniscience. He brings God—who many want to put at a distance—close to home. God’s knowledge of you is personal as it gets. To David, God’s omniscience is not just theological or philosophical—it’s relational and personal. Notice the personal pronouns: “Lord, you have searched me and known me. You know my sitting down and my rising up. You understand my thought afar off” (vs.1–2).

God knows your thoughts even before you think them (vs.3-4). God knows what you really believe about Him, not just what you say about Him. He knows where you stand. He knows your real opinions. He knows your motives. He knows your heart (2 Chronicles 6:30). He knows the real you.

He knows you better than you know yourself. He can see your blind spots; sins of which you are unaware (v.3, 24), or for which you make excuses. Proverbs teaches that God’s knowledge is personal: “All the ways of a man are clean in his own sight, but the Lord weighs the motives” (16:2); “Every man’s way is right in his own eyes, but the Lord weighs the hearts” (21:2). There is also a positive aspect to God’s omniscience: God also sees and approves of your service, even if no one else notices (Hebrews 6:10).

You will never know-it-all, but that is reason to worship.

Do you mind God knowing everything about you? Or do you feel that’s awfully intrusive? When David says “Search me, O God, and know my heart” (Psalm 139:23), it’s a prayer inviting God to know more (even though that’s not possible). That’s a humble and vulnerable prayer. It’s giving Him the key to your darkest parts and inner chambers of your heart.

You might be intelligent. You might be a 4.0 student and aced your SAT. You might be a Ken Jennings and be the best at Jeopardy. The world might label you a genius and honor you with the Noble Prize, but compared with God, you know nothing. Your knowledge is never comprehensive. Nor do you know what is best for your own sake. Ask God to show you the truth about yourself so that He might make you wise (Psalm 139:23–24).

When trying to wrap my brain around God’s omniscience—and all His divine attributes—it it easy to blow a fuse. God’s ability transcends my reality, therefore, it’s best to just bow to His immensity. God is always greater than my present knowledge of Him. If God were small enough for my brains, He wouldn’t be big enough for my needs (cf. Matthew 6:8, 32).

God indeed “knows it all.” By His very nature, without having to learn anything, He already knows everything—past, present, and future. My response to His knowledge: worship and adoration,

“Such knowledge is too wonderful for me; it is high; I cannot attain it.” (Psalm 139:6)

“How precious to me are your thoughts, O God! How vast is the sum of them! If I would count them, they are more than the sand. I awake, and I am still with you.” (Psalm 139:17-18)