Question: "What is the outer darkness in Matthew 22:13?"
Answer: In the Parable of the Wedding Feast, Jesus tells of a “wedding crasher” of sorts: a man in the wedding hall was discovered to have entered the feast without authorization. Jesus says that the king, the master of the feast, issued a dire command concerning the interloper: “Bind him hand and foot and cast him into the outer darkness” (ESV).
Jesus uses the term “outer darkness” in the parable to describe a condition of great sorrow, loss and woe. It stands in vivid contrast to the brightly lit and joyous celebration attended by those who accepted the king’s invitation. Interpreting the wedding feast as heaven, the “outer darkness” must be the place of eternal punishment. Most Bible scholars agree that the phrase “outer darkness” refers to hell or, more properly, the lake of fire (Matthew 8:12; 13:42; 13:50; and 25:23).
The outer darkness of Jesus’ parable is called “blackest darkness” in Jude 1:13. Again, a place of judgment is the obvious meaning, since it is reserved for “godless men” (verse 4).
Perhaps the place of judgment is pictured as “dark” because of the absence of God’s cheering presence. “When you hide your face, they are terrified” (Psalm 104:29). God is called “light” in 1 John 1:5, and if He withdraws His blessing, only darkness is left. Throughout the Scriptures light symbolizes God’s purity, holiness, and glory. Darkness is used as a symbol of moral depravity (Psalm 82:5; Proverbs 2:13; Romans 3:12). Darkness can also refer to trouble and affliction (Job 5:12; Proverbs 20:20; Isaiah 9:2) and to death and nothingness (1 Samuel 2:9; Ecclesiastes 11:8; Job 3:4-6).
The outer darkness of judgment is accompanied by “weeping and gnashing of teeth.” The “weeping” describes an inner pain of the heart, mind, and soul. The word in the original denotes a bewailing or lamentation by beating the breast in an expression of immense sorrow. The “gnashing of teeth” describes an outward pain of the body. Taken together, the weeping and gnashing of teeth says hell is a place of indescribable spiritual agony and unending physical pain (see Luke 16:23-28). The outer darkness is a place of anguish, heartache, grief, and unspeakable suffering. Such will be the lot of all who reject Christ (John 3:18, 36).
Christ is the Light of the World (John 8:12). When one rejects the Light, he will be cast into eternal darkness. Just like the man in the parable, the one who rejects Christ will lose his chance for joy, blessing and fellowship and will be left with nothing but darkness and eternal regret.