And when Abigail saw David, she hasted, and lighted off the ass, and fell before David on her face, and bowed herself to the ground,

Jamieson-Fausset-Brown Bible Commentary

23. she hasted, and lighted off the ass, and fell before David on her face-Dismounting in presence of a superior is the highest token of respect that can be given; and it is still an essential act of homage to the great. Accompanying this act of courtesy with the lowest form of prostration, she not only by her attitude, but her language, made the fullest amends for the disrespect shown by her husband, as well as paid the fullest tribute of respect to the character and claims of David.

Matthew Henry's Concise Commentary

25:18-31 By a present Abigail atoned for Nabal's denial of David's request. Her behaviour was very submissive. Yielding pacifies great offences. She puts herself in the place of a penitent, and of a petitioner. She could not excuse her husband's conduct. She depends not upon her own reasonings, but on God's grace, to soften David, and expects that grace would work powerfully. She says that it was below him to take vengeance on so weak and despicable an enemy as Nabal, who, as he would do him no kindness, so he could do him no hurt. She foretells the glorious end of David's present troubles. God will preserve thy life; therefore it becomes not thee unjustly and unnecessarily to take away the lives of any, especially of the people of thy God and Saviour. Abigail keeps this argument for the last, as very powerful with so good a man; that the less he indulged his passion, the more he consulted his peace and the repose of his own conscience. Many have done that in a heat, which they have a thousand times wished undone again. The sweetness of revenge is soon turned into bitterness. When tempted to sin, we should consider how it will appear when we think upon it afterwards.