What does it mean for God to be omniscient?

The word omniscience comes from the Latin language. It is composed of two parts, a prefix, omni, meaning “all,” and sciens, meaning “to know.” Thus, omniscient means “all-knowing”; God knows all (1 John 3:20). As the All-Knowing One, God did not acquire perfect knowledge through the process of learning. Humans learn one thing after another through a successive program of study and instruction. But God has never learned anything from anyone (Isa. 40:13–14; Rom. 11:33–36).

God is omniscient in virtue of the fact that He is God (1 Sam. 2:3; Ps. 92:5; Rom. 11:33). As such, He knows Himself perfectly (1 Cor. 2:11–12); He knows you—exhaustively, completely, perfectly (Ps. 139:1–6; Job 23:10). He knows your heart (Acts 1:24). And when others have misunderstood you, He knows what your true motives and intentions were and are (John 21:17).

Be encouraged! God knows eternally and from all eternity without succession, all things and everything past, present (Heb. 4:13), future (Isa. 42:9, 44:6–8), and everything probable (Matt. 11:21–23). Because of this, God is never caught off guard, never surprised by some unexpected event. The triune God is the supreme, unique, and incomparable reality! God is complete, whole, perfect, and of infinite knowledge. He is holy, righteous, and good. He always uses His infinite knowledge for His good, holy, and redemptive purpose. In the power of the Spirit, let us follow His example, and use our biblically based knowledge for God’s glory and for Christ’s kingdom.