A possible concise summary is:
Abigail is a wise and beautiful woman who saves her foolish and wealthy husband Nabal from David's wrath. Nabal had insulted David and refused to reward him for protecting his flocks. Abigail intervenes and brings gifts to David, appealing to his faith and future as Israel's king. She persuades him not to shed blood and avenge himself. David praises God for sending Abigail and accepts her request. Nabal dies of a stroke after learning what happened, and David marries Abigail. The summary teaches some relationship lessons from Abigail's example.
Here are some key facts extracted from the text:
1. David sent messengers to nabal, a rich sheep rancher, to ask for some food and hospitality in return for protecting his flocks.
2. Nabal insulted David and refused to give him anything, provoking David's anger and desire for revenge.
3. Abigail, nabal's intelligent and beautiful wife, intervened by bringing a generous gift to David and persuading him not to shed blood.
4. David accepted Abigail's gift and advice, and praised God for sending her to stop him from sinning.
5. Nabal died of a stroke after Abigail told him what she had done, and David married Abigail as his second wife.