Do we really understand the difference between the Aaronic and Melchizedek priesthood? Service is great, and the Aaronic priesthood has power to bring us into the presence of angels. But service, meaning temporal service has not power to bring us into the presence of God. That is because (temporal) service is a principle of the Aaronic priesthood, and is insufficient to obtain the blessings reserved to the principles of the Melchizedek priesthood.
All men feel the influence of the light of Christ when they serve their fellow men in righteousness. The experience that loving grace descending on them and they find their natures and inclinations improved for a time. But that is not a principle sufficient for men to enter heaven. It is a principle of found in honorable men of the earth. But it is not a principle that will open the heavens and bring them into the presence of God. Such blessings are only open through the Melchizedek priesthood.
By saying the Aaronic priesthood has the keys of the gospel of repentance, the scripture means that the teaching in the Aaronic priesthood is principally that of the fundamental principle of repentance. They have a responsibility to declare repentance. They administer the sacrament, which is a powerful spiritual ordinance to repent and reconsider.
The Aaronic priesthood is principally concerned with repentance within the church, for it is by the Melchizedek preisthood that the gospel is carried to the world. Missions are not governed by the Aaronic priesthood, but by the Melchizedek.
The sacrament IS an ordinance of the Aaronic priesthood. If we think, as I have in the past, that the sacrament is as powerful as the ordinances of the Melchizedek priesthood, it may be because we are not enjoying the full power of those ordinances governed by the Melchizedek priesthood, and I am sure that I have not. For surely the ordinance of the lesser priesthood which can be administered by the lesser priesthood is not on a level with the ordinances of the greater priesthood which can only be administered within the Lord's own house, or with that ordinance that grants a man or woman the life altering permanent change in which they receive the gift of the Holy Ghost.
The spiritually transforming works of missionary work and work for the dead are in a different league altogether than the Aaronic work of temporal service. Missionary work is expected of men who are ordained Elders. It is not required of sisters, whose obligations lie in a different direction.
Ministering in spiritual things which save the soul is a greater work than ministering in temporal concerns. And so the Melchizedek priesthood is higher than the Aaronic priesthood.
But until we have the first principles right we cannot fully take hold on the later principles. Until we live the law of consecration, which is a temporal principle, we will never enjoy the Melchizedek priesthood as it is really intended to be manifest.
D&C 70:14 Nevertheless, in your temporal things you shall be equal, and this not grudgingly, otherwise the abundance of the manifestations of the Spirit shall be withheld.
But individuals can live so they have Zion within themselves. What purpose is there to covenanting to live the law of consecration if we cannot choose to live individually so as to attain a measure of its blessings?
Brigham Young said: As individuals, we enjoy Zion at present, but not as a community; there is so much sin, darkness, and ignorance, and the veil of the covering which is over the nations of the earth is measurably over the Latter-day Saints. The same unrighteous principles, which becloud the minds of men universally, more or less becloud the minds of the Latter-day Saints. Though the veil is partially broken to the Saints, though it becomes thin, as it were, and the twilight appears like the dawning of the day, yet we may travel for many years before the sunshine appears. It does not yet appear to this people, they are merely in the twilight.
As one expressed it in ancient times, "We see through a glass, darkly" —through a smoked or dim glass—through which we cannot behold objects clearly with the natural eye.
We have not faith sufficient to have revelation, to have the visions of eternity opened unto us so clearly that we may see things as they are, consequently, we have to live by faith and not by sight. We have to live by the principles of the Gospel, which is faith in the heart and obedience to its requirements.
When the saints live, to some measure, the principles of the Aaronic priesthood, we find the hearts of the Saints knit together in unity and love. This is not just principles of service and other temporal concerns, for without repentance hearts will not be knit together over the long haul. They may have joy in their works for a time without repentance, but without it they must become as the apostate Christian churches in Joseph Smith's day who appeared on the surface to have great love for one another but whose feelings of love were more pretended than real and eventually fall in a tumult of one sort or another, be it a war of opinions or some other contention altogether.
But we as a people live, at best, a part of the principles of the Aaronic priesthood. We don't yet live consecration, which is a temporal matter and governed by the Aaronic priesthood. Therefore the abundance of the manifestations of his spirit are withheld as the scriptures dictate. Some wards barely live the principles of the Aaronic priesthood at all. Some live them much more and there is a tremendous difference there.
But none lives the whole now, or shall until we repent and live consecration.
Incidentally, it may be worth noting that some members have thought that, the Lord having taken away the law of consecration, that it would be wrong for communities of saints to take such a principle on themselves. But that is completely false, as Brigham Young encouraged the saints to live together by consecration. He spoke of some of them successfully doing so at times.
So the Lord has nothing against us learning to live by the principles of the Aaronic priesthood. Or put differently, there is nothing wrong with us learning to live by the law of consecration and thereby enjoying the blessings it bestows if a community of saints determines that they are committed to doing so.