Commentaries:
Robertson's Word Pictures (NT)
As for these things (tauta). Accusative of general reference.
One stone upon another (liqov epi liqw). Stone upon stone (locative). Here both Mark 13:2; Matthew 24:2 have epi liqon (accusative). Instead of ouk afeqhsetai (future passive) they both have ou mh afeqh (double negative with aorist passive subjunctive). It was a shock to the disciples to hear this after the triumphal entry.
Other Robertson's Word Pictures (NT) entries containing Luke 21:6:
Revelation 11:1
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