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“Verily I say unto you, This generation shall not pass, till all these things be fulfilled” (Matthew 24:34).
The disciples asked Jesus, “what shall be the sign of thy coming, and of the end of the world” (Matthew 24:3). Jesus answered and spoke of future events. The generation of people living when those events that He described in Matthew 24 and 25 is the generation that Jesus speaks of “not passing” until He returns.
Commentators, generally, have observed that the expression “this generation” of Matthew 23:36 refers to the generation of the apostles. Jesus repeatedly used the expression “this generation” in this sense (Matthew 11:16; 12:39, 41, 42, 45; 16:4; 17:17; etc). Obviously, Christ’s predictions concerning the fall of Jerusalem, which occurred in A.D. 70, did, literally, come to pass within the lifetime of many the disciples.
However, the words “this generation” in Matthew 24: 34 are in the context of vs. 27–51, which deal exclusively with the coming of the Son of man at the end of the world. The signs mentioned in these verses and in Luke—“signs” in the heavens and “upon the earth” (Luke 21:25)—would take place so near the day of His coming that Christ declared that the “generation” that sees the last of the signs, shall not pass before “all these things [Christ’s coming and the end of the world] be fulfilled.”
Christ did not intend that His followers should know the exact date when He would return. The signs foretold would testify to the nearness of His coming, but, He declared, the “day and hour” of that event “knoweth no man” (Matthew 24:36). To make the expression, “this generation,” the basis for figuring a period of time supposedly terminating with His return violates His words and His instructions (vs. 36, 42).