I was wondering how Russell in the old days explained this. In the Reprints, I have not found it in the Index keywords. Nevertheless, there was a first mention in the Sep 1st, 1901 issue
WHAT WAS JEPHTHAH'S VOW?
Question.--What attitude are we to assume toward the account of Jephthah's reckless vow which brought death to his daughter? Is there any redeeming feature in the incident?
Answer.--We are to accept the scriptural statement that Jephthah was amongst the faithful--acceptable to God. As such he must also be acceptable to us. In respect to his offering his daughter in sacrifice our conclusion must be that the divine arrangement then and now differs materially. We may say, however, that as Abraham was about to offer his son Isaac, not willingly, but through obedience to what he understood to be the divine will, so did Jephthah with his daughter; and he was not hindered by an angel from the Lord. I do not know if the lamentation has any significance.
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Answer.--A totally different view of this matter is possible, and we merely suggest it; namely, that the vow was one of full devotion to the Lord--one of chastity and sanctity--seclusion from society, deadness to the world as a priestess. The daughter's request for time for lamentation, and the subsequent annual celebration by the virgins, would agree well with this view. The chief objection to this view is the statement respecting "a burnt offering," and this seems almost insurmountable."
It was taken up again in Oct 15th, 1901:
JEPHTHAH'S VOW – A BETTER TRANSLATION. In our September first issue we answered a question respecting Jephthah's daughter. Since then Brother C. J. Peterson calls to our attention the following item from the Appendix of the Emphatic Diaglott. "The original, Judges 11:30, when properly translated, reads thus: 'And it shall be that whoever comes forth of the doors of my house to meet me, when I return in peace, from the children of Ammon, shall surely be Jehovah's, and I will offer to him a burnt offering.' The vow contains two parts: (1) That person who would meet him on his return should be Jehovah's, and be dedicated forever to his service, as Hannah devoted Samuel before he was born. (1 Sam. 1:11.) (2) That Jephthah himself would offer a burnt offering to Jehovah. "Human sacrifices were prohibited by the Law (Deut. 12:30); and the priests would not offer them. Such a vow would have been impious, and could not have been performed. It may be safely concluded that Jephthah's daughter was devoted to perpetual virginity; and with this idea agrees the statements that 'she went to bewail her virginity;' that the women went four times in every year to mourn or talk with (not for) her; that Jephthah did according to his vow, and that 'she knew no man.'" We are glad that our attention is called to this evidently better translation, which clears away the difficulty, and shows that the burnt-offering was one thing, and the devotion of the daughter another thing. We are to remember, too, the testimony of the entire Old Testament, to the effect that prior to our Lord's birth all the women of Israel coveted earnestly the great blessing and privilege of being possibly the mother of Messiah, or amongst his forebears. We are to remember, also, the exultant language of the Virgin Mary when finally it was announced to her that she had won this long-sought prize: "Henceforth all shall call me blessed" – all shall recognize me as the one who has attained this blessed privilege of being the mother of Messiah."
The Photodrama of Creation included later:
"Jephthah’s daughter was not sacrificed in death as a fulfilment of her father’s vow. She merely took the vow of perpetual virginity and figuratively became dead to the world after spending a brief season with her virgin friends. The Bible is simple and reasonable when understood.—Judges 11:30-40. The overthrow of the Midianites by Gideon’s band and Jephthah’s dedication of his daughter to the Lord in perpetual virginity, belong to the period of the Judges, of whom Joshua was first.—Acts 13:19, 20.
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