1 Samuel 25:43

David also took Ahinoam— Ahinoam is always mentioned as first of the wives of David. See chap. 1 Samuel 27:3 1 Samuel 30:5, &c. And, therefore, it is supposed, that he was married to her before he took Abigail. Polygamy was a practice too prevalent in those ages, even under the dark Jewish dispensation; and David, probably, hoped to strengthen his interest in his own tribe by this double alliance, especially when he apprehended that it must be considerably weakened in that of Benjamin, by Michal's being taken away from him, 1 Samuel 25:44. For Saul had given Michal his daughter, David's wife, to Phalti the son of Laish, a Benjamite; which Saul did to take away all his pretensions to the crown from that alliance.

Remarks on the Character of Samuel.

How singular was the character and piety of Samuel! Devoted to God from the womb, and worthy to be so! Early dedicated to the Divinity, and hallowed by his influence! Descended from prophets, himself a greater prophet. The peculiar service of God constituted the early business of his life; nor was it ever interrupted by any thing but the service of his country.
The Scriptures are certainly the solace of life; but the pleasure of perusing them is always heightened when they demonstrate their own veracity. No man, guided by nature only, in the vigour of life, and in the age of ambition and avarice, forced by no danger, urged by no guilt, and pressed by no infirmity of mind or body, ever yet, voluntarily, and of his own choice, resigned the supreme power, secluded his sons from the succession, and elected two strangers to it, in succession, neither of whom he had ever seen before. Samuel did all this; and therefore, when the Scriptures assure us that he did it by the divine command, we cannot help believing them: the narration carries with it its own irresistible evidence.
Happy Samuel! Exalted to supreme power without ambition; exerting it without oppression or avarice; and resigning it without reluctance, when his God commanded! Retiring (rare felicity!) with undiminished dignity, or, to speak more justly, with added honour, from the concurrent and universal testimony of his country to his equity and incorruption! Oh, that all princes would so use their power, or so resign it! Illustrious in the splendor of authority, and yet more so in the shade of a cell; so far from envying his successor to the supreme power, he pitied and prayed for him! He had raised him by the divine favour, but could not restore him.
It would be hard to decide which was happiest, his life, or his death. He lived to the noblest of purposes, the glory of God, and the good of his country; he died full of years and honours, universally lamented and desired. Such was Samuel! Such always were, and always will be, those, whose duty is their delight, and whose God is their glory!