Thanks to DH, I've discovered that there is indeed authoritative support for the notion that women are more spiritual than men. From some preliminary searches, it seems that this idea is a relatively recent innovation in the Church.
From the Church's earliest days, its leaders championed the equality of women in spiritual matters. Although the Prophet Joseph and many who followed him noted the propensity of women for "feelings of charity and benevolence," I have found no indication that these early leaders felt that women had a greater natural spiritual endowment than men. John A. Widtsoe clarified that the priesthood was not given on the basis of capability, competency or excellence, but as a gift. He said,
"Women of a congregation … may be wiser, far greater in mental powers, even greater in actual power of leadership than the men who preside over them. That signifies nothing. The Priesthood is not bestowed on the basis of mental power but is given to good men and they exercise it by right of divine gift, called upon by the leaders of the Church. Woman has her gift of equal magnitude.” (John A. Widtsoe, Priesthood and Church Government, Salt Lake City: Deseret Book Co., 1954, p. 90).
This equality between the sexes in spirituality was preached until the end of the 1970's. Elder Bruce R. McConkie declared in Nauvoo at the dedication of the Monument to Women:
“Where spiritual things are concerned, as pertaining to all of the gifts of the Spirit, with reference to the receipt of revelation, the gaining of testimonies, and the seeing of visions, in all matters that pertain to godliness and holiness and which are brought to pass as a result of personal righteousness in all these things men and women stand in a position of absolute equality before the Lord. He is no respecter of persons nor of sexes, and he blesses those men and those women who seek him and serve him and keep his commandments.” (Bruce R. McConkie, Ensign, Jan. 1979, p. 61.)
One of the first comments about a special spiritual sensitivity on the part of women that I have been able to find came from Neal A. Maxwell. In explaining women's roles in the Church and in they eyes of God he cited some of the notable women of the Bible:
"When we would measure loving loyalty in a human relationship, do we not speak of Ruth and Naomi even more than David and Jonathan?... A widow with her mite taught us how to tithe. An impoverished and starving widow with her hungry son taught us how to share, as she gave her meal and oil to Elijah. The divine maternal instincts of an Egyptian woman retrieved Moses from the bullrushes, thereby shaping history and demonstrating how a baby is a blessing—not a burden... Does it not tell us much about the intrinsic intelligence of women to read of the crucifixion scene at Calvary, "And many women were there beholding afar off." (Matt. 27:55.) Their presence was a prayer; their lingering was like a litany. And who came first to the empty tomb of the risen Christ? Two women. Who was the first mortal to see the resurrected Savior? Mary of Magdala. Special spiritual sensitivity keeps the women of God hoping long after many others have ceased" (Neal A. Maxwell, "The Women of God," Ensign, May 1978, 10).
Also about this time, Spencer W. Kimball also began to extol the virtues of womanhood. He made the following comment, which can be construed to mean that women have more of a natural inclination toward spirituality than men, and thus are more likely to join the Church:
"...much of the major growth that is coming to the Church in the last days will come because many of the good women of the world (in whom there is often such an inner sense of spirituality) will be drawn to the Church in large numbers. This will happen to the degree that the women of the Church reflect righteousness and articulateness in their lives and to the degree that women of the Church are seen as distinct and different—in happy ways—from the women of the world." (Spencer W. Kimball, Ensign, Nov. 1979, pp. 103–104).
Perhaps the greatest champion of women's greater spiritual capacity was James E. Faust. He gave many talks for and about women beginning in the 1980's. Some of these included
Womanhood: The Highest Place of Honor,
What it Means to be a Daughter of God, and
You Are All Heaven-Sent.
President Faust repeatedly told women that they had an inner spiritual strength that surpassed that of men. See DH's blog post for several quotes by President Faust along these lines.
President Faust's ideas were reiterated by several of the other Apostles. Boyd K. Packer said that men and women are by nature different, and while they share many basic human traits, the “virtues and attributes upon which perfection and exaltation depend come [more] naturally to a woman.” (Boyd K. Packer, For Time and All Eternity,” Ensign, Nov. 1993, 22).
M. Russell Ballard told women,
"Now, finally, I turn again to you dear sisters, you who have such a profound, innate spiritual ability to hear the voice of the Good Shepherd. You need never wonder again if you have worth in the sight of the Lord and to the Brethren in the presiding councils of the Church. We love you. We cherish you. We respect you. Never doubt that your influence is absolutely vital to preserving the family and to assisting with the growth and spiritual vitality of the Church. This Church will not reach its foreordained destiny without you. We men simply cannot nurture as you nurture. Most of us don’t have the sensitivity—spiritual and otherwise—that by your eternal nature you inherently have. Your influence on families and with children, with youth, and with men is singular. You are natural-born nurturers. Because of these unusual gifts and talents, you are vital to taking the gospel to all the world, to demonstrating that there is joy in living the way the prophets have counseled us to live." (M. Russell Ballard, “Women of Righteousness,” Ensign, Apr 2002, 73).
These teachings by the General Authorities have been repeated by local leaders and members and sometimes used to promote the idea that the priesthood is given to men to compensate for his lesser spiritual ability. It is also said that the priesthood can help men develop spirituality, a gift that women do not need since their spirituality is innate. This idea has been repeated despite the lack of prophetic approbation. Apparently this year (2007) marks the first time a General Authority has espoused linking the Priesthood and a woman's spirituality. An article by Bruce C. Hafen, a member of the Quorum of the Seventy in a recent Ensign reads:
"Spouses need not perform the same functions to be equal. The woman’s innate spiritual instincts are like a moral magnet, pointing toward spiritual north—except when that magnet’s particles are scrambled out of order. The man’s presiding gift is the priesthood—except when he is not living the principles of righteousness. If the husband and the wife are wise, their counseling will be reciprocal: he will listen to the promptings of her inner spiritual compass just as she will listen to his righteous counsel." (Bruce C. Hafen and Marie K. Hafen, “Crossing Thresholds and Becoming Equal Partners,” Ensign, Aug 2007, 24–29).
The study of the words of these recent General Authorities shows a mainstream doctrinal expression that women are endowed with an innate spiritual gift. It is certainly a beautiful thought as worded by Maxwell and Hafen. However, I wonder at the wisdom of proclaiming that the bestowal of the Priesthood upon the male sex is compensatory. I object to the idea that Priesthood is given to the less spiritually inclined to help them "catch up." Look at the way Priesthood works among men: it is not given to the less spiritual among males to help them become stronger. Rather, men who have already proved worthy are ordained to Priesthood offices so that they may lead, serve, bless, and speak in the name of God.
I would like to explore these ideas further. I am especially interested to know if there are any statements about women's greater spirituality coming from authoritative sources before 1978. Was this idea expounded at all before the time of the Women's Movement in the '70's? If not, what was the reason for the doctrinal shift?