A.T. Robertson Commentary Luke 11:29

"And when the multitudes were gathering together unto him, he began to say, This generation is an evil generation: it seeketh after a sign; and there shall no sign be given to it but the sign of Jonah." — Luke 11:29 (ASV)

Were gathering together unto him (επαθροιζομενων). Genitive absolute present middle participle of επαθροιζω, a rare verb, Plutarch and here only in the N.T., from επ and αθροιζω (a common enough verb). It means to throng together (αθροος, in throngs). Vivid picture of the crowds around Jesus.

But the sign of Jonah (ε μη το σημειον Ιωνα). Luke does not give here the burial and resurrection of Jesus of which Jonah's experience in the big fish was a type (Matthew 12:39ff.), but that is really implied (Plummer argues) by the use here of "shall be given" (δοθησετα) and "shall be" (εστα), for the resurrection of Jesus is still future. The preaching of Jesus ought to have been sign enough as in the case of Jonah, but the resurrection will be given. Luke's report is much briefer and omits what is in Mt 12:41.