A.T. Robertson Commentary Luke 20:41

"And he said unto them, How say they that the Christ is David`s son?" — Luke 20:41 (ASV)

How say they? (Πως λεγουσιν; ). The Pharisees had rallied in glee and one of their number, a lawyer, had made a feeble contribution to the controversy which resulted in his agreement with Jesus and in praise from Jesus (Matthew 27:34–40). Luke does not give this incident which makes it plain that by "they say" (λεγουσιν) Jesus refers to the Pharisees (rabbis, lawyers), carrying on the discussion and turning the tables on them while the Pharisees are still gathered together (Matthew 22:41). The construction with λεγουσιν is the usual infinitive and the accusative in indirect discourse. By "the Christ" (τον Χριστον) "the Messiah" is meant.