More similar comments from sound commentators, not hard to look up,

Matthew Poole:

Answer: What we call day and night made up the Jewish nychtemerai;. It appears by Gen 1:5, that the evening and the morning made up a day. Three days and three nights is with us but the same thing with three natural days, and so it must be understood here. Christ was in the grave three natural days, that is, part of three natural days; every one of which days contained a day and a night, viz. twenty-four hours.

Matthew Henry:

He (Christ) continued in the grave just as long as Jonah continued in the fish's belly, three days and three nights; not three whole days and nights: it is probable, Jonah did not lie so long in the whale's belly, but part of three natural days (nychthemerai, the Greeks called them); he was buried in the afternoon of the sixth day of the week, and rose again in the morning of the first day; it is a manner of speech very usual;

see 1Ki 20:29
And they pitched one over against the other seven days. And so it was, that in the seventh day the battle was joined: and the children of Israel slew of the Syrians an hundred thousand footmen in one day.

Est 4:16; Est 5:1; Luk 2:21 So long Jonah was a prisoner for his own sins, so long Christ was a Prisoner for ours.

Albert Barnes

Three days and three nights - It will be seen in the account of the resurrection of Christ that he was in the grave but two nights and a part of three days. This computation is, however, strictly in accordance with the Jewish mode of reckoning. If it had “not” been, the Jews would have understood it, and would have charged our Saviour as being a false prophet, for it was well known to them that he had spoken this prophecy,

 Mat 27:63
Saying, Sir, we remember that that deceiver said, while he was yet alive, After three days I will rise again.

Such a charge, however, was never made; and it is plain, therefore, that what was “meant” by the prediction was accomplished. It was a maxim, also, among the Jews, in computing time, that a part of a day was to be received as the whole. Many instances of this kind occur in both sacred and profane history.

See 2Ch 10:5
And he said unto them, Come again unto me after three days. And the people departed

 2Ch 10:12
So Jeroboam and all the people came to Rehoboam on the third day, as the king bade, saying, Come again to me on the third day. 

 Gen 42:17-18
17 And he put them all together into ward three days. 18 And Joseph said unto them the third day, This do, and live; for I fear God

Compare Est 4:16 with Est 5:1.

Last edited by AlexM; Mon Jan 07, 2019 12:39 PM.