And Saul said to David, Behold my elder daughter Merab, her will I give you as your wife: only be you valiant for me, and fight the LORD'S battles. For Saul said, Let not my hand be upon him, but let the hand of the Philistines be upon him.
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Because Saul was anointed with a holy chrism and given governorship over the kingdom, he preserved himself as a type of Christ. At that time we understood his two daughters to be two peoples, which were begotten by the twofold faith and love for Christ for salvation, namely, of the body and the mind, and made perfect by discipline. We understood the elder daughter to refer to the synagogue and the younger daughter the church. However, because the circumstances have changed in this passage, inasmuch as David represents Christ the Lord and Saul represents the people of the Jews who envied him, the older daughter who was promised but not given, means that portion of the same people which is more numerous and powerful and was promised to the brave and desirable bridegroom. When the predecessors of that portion of the Israelites (that is to say, the scribes, priests, Pharisees and elders of the people) came together to hear him, they called him a good teacher—and what is more, a singularly ...
And Saul. This and the two following verses are omitted in the Roman Septuagint, which subjoins, "and Michol, the daughter of Saul, loved David "(Haydock)
Wife. He had promised her already, (Menochius) if the verses in the preceding chapter be genuine. But why then had he delayed so long, and why does he require other conditions? The comparison made by the women, (ver. 7,) and the inconstant temper of Saul, might account for this. (Haydock)
The Lord defends his people. As long as the Israelites followed the orders of God, their wars might justly be attributed to him; but not when they were waged to satisfy the cravings of ambition. (Calmet)