Jamieson, Fausset and Brown on Luke 11:47-48

47-48. ye build, &c.--Out of pretended respect and honor, they repaired and beautified the sepulchres of the prophets, and with whining hypocrisy said, "If we had been in the days of our fathers, we should not have been partakers with them in the blood of the prophets," while all the time they "were witnesses to themselves that they were the children of them that killed the prophets" (Mt 23:29, 30); convicting themselves daily of as exact a resemblance in spirit and character to the very classes over whose deeds they pretended to mourn, as child to parent.