Acts 13:20

And after that he gave unto them judges about the space of four hundred and fifty years - This is a most difficult passage, and has been termed by Scaliger, Crux Chronologorum. The apostle seems here to contradict the account in 1Ki 6:1: And it came to pass in the four hundred and eightieth year after the children of Israel were come out of the land of Egypt, in the fourth year of Solomon’s reign, he began to build the house of the Lord.

Taking the words as they stand in the Greek, thus, "after that, by the space of four hundred fifty years, He gave judges," the meaning may be, that about four hundred fifty years elapsed from the time of the covenant with Abraham until the period of the judges; which is historically correct, the word "about" showing that chronological exactness was not aimed at.

He gave unto them judges - Men who were raised up in an extraordinary manner to administer the affairs of the nation, to defend it from enemies, etc. See Jdg 2:16. About the space of four hundred and fifty years - This is a most difficult passage, and has exercised all the ingenuity of chronologists. The ancient versions agree with the present Greek text. The difficulty has been to reconcile it with what is said in 1Ki 6:1, “And it came to pass in the four hundred and eightieth year after the children of Israel were come out of the land of Egypt, in the fourth year of Solomon’s reign over Israel ...he began to build the house of the Lord.” Now if to the 40 years that the children of Israel were in the wilderness there be added the 450 said in Acts to have been passed under the administration of the judges, and about 17 years of the time of Joshua, 40 years for Samuel and the reign of Saul together, and 40 years for the reign of David, and three years of Solomon before he began to build the temple, the sum will be 590 years, a period greater by 110 years than that mentioned in 1Ki 6:1. Various ways have been proposed to meet the difficulty. Doddridge renders it, “After these transactions, (which lasted) 450 years, he gave them a series of judges,” etc., reckoning from the birth of Isaac, and supposing that Paul meant to refer to this whole time. But to this there are serious objections: (1) It is a forced and constrained interpretation, and one manifestly made to meet a difficulty. (2) There is no propriety in commencing this period at the birth of Isaac. That was in no manner remarkable, so far as Paul’s narrative was concerned; and Paul had not even referred to it. This same solution is offered also by Calovius, Mill, and DeDieu. Luther and Beza think it should be read 300 instead of 400. But this is a mere conjecture, without any authority from mss. […]