Judges 11:9, 10: The Elders' Solemn Vow to Jephthah
Verse 9: And Jephthah said unto the elders of Gilead, If ye bring me home again to fight against the children of Ammon, and the LORD deliver them before me, shall I be your head?
[If ye be come to me in sincerity, אִם־מְשִׁיבִ֙ים אַתֶּ֤ם אוֹתִי֙] If ye bring me back (Munster, Pagnine, Tigurinus). To go back, in the place of, to go, as already mentioned. I would prefer, ye persuade. For they were not bringing him back to this war, but they were trying to persuade him with reasons (Drusius).
If ye bring me home again; if you recall me from this place where I am now settled, to the place whence I was expelled.
[Shall I be your prince?] That is to say, Have ye promised this to me in earnest and sincerely (Bonfrerius)? Question: Whether Jephthah here was guilty of ambition? Response: This is denied. It is ambition, when the Magistracy is sought by bribery, deceit, and malicious arts. These things Jephthah does not do. But, when one sees himself called to Magistracy with an honest condition interposed, and is able to benefit the Republic, this is not ambition (Martyr). This was an honest oration and a modest request. For he asks only that which they also were able to give, and had previously determined in their council that they were going to give, and now voluntarily and willingly offered (Menochius). [Others otherwise:] There was some measure of ambition in this man, in other respects not evil, nor impious: the Lord chastened it with His paternal rod, as we shall point out (Osiander).
Shall I be your head? will you really make good this promise? Jephthah was so solicitous in this case, either from his zeal for the public good, which required that he should be so; or from the law of self-preservation, that he might secure himself from his brethren; whose ill will he had experienced, and whose injuries he could not prevent, if, after he had served their ends, he had been reduced to his private capacity: or there might be some tincture of ambition in him; for which God therefore severely, though paternally, chastiseth him, as we see afterwards.
Verse 10: And the elders of Gilead said unto Jephthah, (Jer. 42:5) The LORD be witness between us (Heb. be the hearer between us), if we do not so according to thy words.
The LORD be witness between us, etc.: They confirm their promise by a solemn and sacred oath.
 Hebrew: וַיֹּ֙אמֶר יִפְתָּ֜ח אֶל־זִקְנֵ֣י גִלְעָ֗ד אִם־מְשִׁיבִ֙ים אַתֶּ֤ם אוֹתִי֙ לְהִלָּחֵם֙ בִּבְנֵ֣י עַמּ֔וֹן וְנָתַ֧ן יְהוָ֛ה אוֹתָ֖ם לְפָנָ֑י אָנֹכִ֕י אֶהְיֶ֥ה לָכֶ֖ם לְרֹֽאשׁ׃
 Hebrew: וַיֹּאמְר֥וּ זִקְנֵֽי־גִלְעָ֖ד אֶל־יִפְתָּ֑ח יְהוָ֗ה יִהְיֶ֤ה שֹׁמֵ֙עַ֙ בֵּֽינוֹתֵ֔ינוּ אִם־לֹ֥א כִדְבָרְךָ֖ כֵּ֥ן נַעֲשֶֽׂה׃
 Hebrew: יִהְיֶ֤ה שֹׁמֵ֙עַ֙ בֵּֽינוֹתֵ֔ינוּ.