Are Jesus' words in Matthew 23:37 regarding Jerusalem killing prophets about past murders (which are not documented in history prior to the first century) or to the persecution that he and his disciples would (and did) experience in the first century, ala Matthew 23:34?
[Mat 23:29-38 KJV] (29) Woe unto you, scribes and Pharisees, hypocrites! because ye build the tombs of the prophets, and garnish the sepulchres of the righteous, (30) And say, If we had been in the days of our fathers, we would not have been partakers with them in the blood of the prophets. (31) Wherefore ye be witnesses unto yourselves, that ye are the children of them which killed the prophets. (32) Fill ye up then the measure of your fathers. (33) Ye serpents, ye generation of vipers, how can ye escape the damnation of hell? (34) Wherefore, behold, I send unto you prophets, and wise men, and scribes: and some of them ye shall kill and crucify; and some of them shall ye scourge in your synagogues, and persecute them from city to city: (35) That upon you may come all the righteous blood shed upon the earth, from the blood of righteous Abel unto the blood of Zacharias son of Barachias, whom ye slew between the temple and the altar. (36) Verily I say unto you, All these things shall come upon this generation. (37) O Jerusalem, Jerusalem, thou that killest the prophets, and stonest them which are sent unto thee, how often would I have gathered thy children together, even as a hen gathereth her chickens under her wings, and ye would not! (38) Behold, your house is left unto you desolate.