When the lord therefore of the vineyard cometh, what will he do unto those husbandmen?

whenever therefore the lord of the vineyard may come, what will he do to these husbandmen?'

When then the owner of the vineyard comes, what will he do to those vine-dressers?"

When, then, the lord of the vine-garden comes, what will he do to those workmen?

Therefore, when the lord of the vineyard arrives, what will he do to those farmers?"

Now, when the owner of the vineyard comes, what will he do to those tenants?"

When the lord, therefore - Jesus then asked them a question about the proper way of dealing with those people.
The design of asking them this question was that they might condemn themselves, and admit the justice of the punishment that was soon to come upon them.

When the Lord therefore of the vineyard cometh,.... In a way of providence, to call these husbandmen to an account; not only for the fruit they were to bring to him; but for their barbarity to his servants, the prophets, time after time; and especially, for the inhuman usage and murder of his own son,
what will he do unto those husbandmen? This question is put to the chief priests, elders, and Scribes: and they themselves, who are designed hereby, are made judges in this case, just as the inhabitants of Jerusalem and men of Judah are, in Isaiah 5:4 which passage of Scripture our Lord had greatly in view when he spake this parable.

When the lord therefore of the vineyard cometh--This represents "the settling time," which, in the case of the Jewish ecclesiastics, was that judicial trial of the nation and its leaders which issued in the destruction of their whole state.
what will he do unto those husbandmen?

When the lord . . . cometh, what will he do? This question is addressed to the Jews, who seem to have been so carried away by the vivid description that they answered without seeing that they pronounced their own sentence (see Matthew 21:41).