And it came to pass at the time when Merob the daughter of Saul should have been given to David, that she was given to Hadriel the Molathite to wife.

And it cometh to pass, at the time of the giving of Merab daughter of Saul to David, that she hath been given to Adriel the Meholathite for a wife.

But when the time came to give Merab, Saul's daughter, to David, she was given to Adriel of Meholath.

But it happened at the time when Merob, Saul's daughter, should have been given to David, that she was given to Adriel the Meholathite as wife.

Then it happened that, at the time when Merab, the daughter of Saul, was to be given to David, she was given to Adriel, the Meholathite, as wife.

Adriel the Meholathite - The five sons of this marriage perished by the hands of the Gibeonites (marginal reference), where we learn further that the name of Adriel's father, or ancestor, was Barzillai. His birth-place was Meholah, probably the same as Abel-Meholah. (See 1-Kings 19:16 note).

But it came to pass at the time when Merab Saul's daughter should have been given to David, that (h) she was given unto Adriel the Meholathite to wife.
(h) By whom he had five sons who David put to death at the request of the Gibeonites, (2-Samuel 21:8).

But it came to pass, at the time when Merab, Saul's daughter,
should have been given to David,.... Either when the giving of her to him was talked of, or when the time fixed for her marriage was come:
that she was given to Adriel the Meholathite to wife: Saul either having in reality never designed she should be given to David, only proposed it to please the people, or to affront David, and expose him to shame and confusion by the step he meant to take, or however he soon changed his mind; though Abarbinel's notion is, that the young lady had disposed of herself to this person without her father's knowledge, which seems not likely; the person she was given to was the son of Barzillai the Meholathite, 2-Samuel 21:8; and some have observed, as the curse of God on this match, that all her sons were delivered to the Gibeonites, and hanged up, as related in the same place; for though these sons are said to be brought up by Michal, they were bore by Merab to him.

But Saul did not keep his promise. When the time arrived for its fulfilment, he gave his daughter to Adriel the Meholathite, a man of whom nothing further is known.
(Note: 1-Samuel 18:17-19 are omitted from the Septuagint version; but they are so, no doubt, only because Saul's first promise was without result so far as David was concerned.)

Adriel - The son of Bar - zillai, as he is called, 2-Samuel 21:8. This was an act of great injustice; and accordingly this marriage was accursed by God, and the children begotten in it, were, by God's appointment cut off, 2-Samuel 21:8-9.