Vincent's NT Word Studies
29. Were gathered thick together (epaqroizomenwn). The present participle; and therefore, as Rev., were gathering together unto him, or upon him (epi). Only here in New Testament.Evil. See on adulterous. Matt. xii. 39.
Robertson's NT Word Studies
11:29 {Were gathering together unto him} (epaqroizomenwn). Genitive absolute present middle participle of epaqroizw, a rare verb, Plutarch and here only in the N.T., from epi and aqroizw (a common enough verb). It means to throng together (aqroos, in throngs). Vivid picture of the crowds around Jesus. {But the sign of Jonah} (ei me to semeion iwna). Luke does not give here the burial and resurrection of Jesus of which Jonah's experience in the big fish was a type (#Mt 12:39ff.), but that is really implied (Plummer argues) by the use here of "shall be given" (doqesetai) and "shall be" (estai), 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.