Expositor's Bible Commentary Commentary Luke 17:24

"for as the lightning, when it lighteneth out of the one part under the heaven, shineth unto the other part under heaven; so shall the Son of man be in his day." — Luke 17:24 (ASV)

Jesus continues the emphasis on the suddenness of the kingdom’s coming. “One of the days” probably refers to the initiation of the reign of the coming Son of Man (i.e., “his day” in v.24, or “the Day of the Lord”; cf. Amos 8:11, 13 for similar interchange of “days” and “day”). When that day arrives, his coming will be obvious, “like the lightning”; thus rumors of seeing him in various places cannot be true.

The inclusion of the passion prediction (v.25) is natural in Luke, who stresses the order of suffering before glory (cf. 24:26, 46; Acts 17:3). “This generation” may obliquely refer back to the Pharisees. More broadly it refers to Jesus’ contemporaries, elsewhere called by him “unbelieving and perverse” (9:41) and “wicked” (11:29).