Outer darkness is mentioned 3 times in Matthew. Weeping and gnashing of teeth is also mentioned in the 3 verses.
[Mat 8:12 KJV] 12 But the children of the kingdom shall be cast out into outer darkness: there shall be weeping and gnashing of teeth. [Mat 22:13 KJV] 13 Then said the king to the servants, Bind him hand and foot, and take him away, and cast [him] into outer darkness; there shall be weeping and gnashing of teeth. [Mat 25:30 KJV] 30 And cast ye the unprofitable servant into outer darkness: there shall be weeping and gnashing of teeth.https://en.wikipedia.org/wiki/Outer_darkness
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