Bret Stephens (behind wall) makes the case that Hezbollah would best serve its own interests by going along with a cease-fire:

As a matter of strategy, however, Mr. Nasrallah would do well to exercise restraint. Politically, his stock can go no higher; if the war really ends tomorrow, he will emerge not only as the clear victor against Israel but as the de facto master of Lebanon. The international community will be required to consult, court and ultimately legitimize him as the details of this resolution — as well as a subsequent one spelling out the remit of an international force for southern Lebanon — are put into place. That could take weeks or months. In the meantime, Israel would lose the military and political initiative, demobilize its reserves and begin to withdraw its forces. The Lebanese government of Fuad Siniora, formerly an ally of the U.S. and an opponent of Syria — would also be brought to heel, as it would be entirely dependent on Mr. Nasrallah’s say-so to implement a resolution to which it is ostensibly a party.
Nor would Mr. Nasrallah be forced to abide by the terms of the resolution, which, on the face of it, are broadly hostile to his interests. The resolution demands that Hezbollah withdraw from its positions in southern Lebanon and that it disarm. It also imposes an international arms embargo on Hezbollah “except as authorized by its government” and demands the “elimination of foreign forces in Lebanon,” which means not only Israel but also the hundreds of elite Iranian troops who have long trained and equipped, and in recent weeks fought alongside, Hezbollah.
But why should a resolution that merely regurgitates demands made, and never enforced, by the Taif Accords of 1989 and U.N. Resolution 1559 of 2004 succeed this time?…