The beginning verse of 1 Samuel 25 tells us that Samuel has died. Samuel was the last of the judges and the person who established the monarchy in Israel; he was beloved, and likely caused quite a bit of mourning in the land. After Samuel dies, David is back on the run from Saul. 1 Samuel 25 details the rift between David and a man named Nabal, followed by the marriage of David to Nabal's widow, Abigail.
Nabal was a descendant of Caleb (Joshua's friend; he and Joshua were the only Israelites from their generation to enter the promised land). Nabal was a wealthy man living in Carmel, and apparently at one point David helped Nabal. Now, David was asking for Nabal's help in return. Nabal, however, refuses. He arrogantly claims he doesn't know David or his men. As you would expect, David is angered by Nabal's response. David was ready to fight over the matter.
Meanwhile, one of Nabal's men confides in Abigail, Nabal's wife, what has transpired. Abigail realizes that her husband is in the wrong, so she loads up on bread, wine, sheep, corn, raisins, and figs, then sends her servants to David with the goods, all behind her husband's back. Abigail asks for David's forgiveness, which he obliges. David is content not having to kill Nabal; he turns the matter over to God's hand. Shortly after, Nabal gets drunk during a feast. It is after he sobers from this feast that Abigail tells Nabal what has happened. It appears that he has some type of stroke and dies ten days later.
Behavior of a Wife
It's interesting that Abigail is praised for doing the right thing by going behind her husband's back to make things right. Many people get hung up on the idea that women are to be submissive to their husbands and miss the actual message given about marriage in the Bible. Wives were to be the rock and strength of the husband, which included helping them. Sometimes helping people requires doing something they don't want you to do. Think about it, are you a better friend if you tell your teenage friend's parents that he/she is secretly experimenting with drugs, or if you simply allow them to continue? Abigail chose to save her husband's life (at least from the hands of David) by completing the transaction he was obligated to. This is yet another passage that should force people to re-evaluate their view of women in the Bible and a wife's role.
Wives of David
When David learns of Nabal's death, he sends for Abigail to become his wife. Abigail was said to have been of beautiful countenance (as was David). This union gave David a great deal of resources. David also takes a woman named Ahinoam as his wife, though the timeline of this is not given. It is in 1 Samuel 25:44 that we learn Saul has given David's wife Michal to Phalti, the son of Laish. We aren't told if this happens before or after David takes on more wives, nor if this change takes place according to Michal's will or according to Saul's will.