One of the things that were taught in the early church but that people seem to consider an embarrassment in these days is the doctrine of blood atonement.
But it is not an embarrassing doctrine at all. It is badly misunderstood, to be sure. And as protestant ideas about the atonement have been being popularized among many church members it becomes more foreign to us, as it is clearly at odds with such teachings. But it is a perfectly good doctrine, and not at all what it is commonly portrayed as.
The typical portrayal of this doctrine is this: for a man or woman who commits adultery to be saved their blood must be shed, i.e. they must be killed.
Now Brigham Young clearly recognized that some of the things he had taught could be misconstrued as meaning that. He said "From what is at times said here, it might be inferred that everyone who did not walk to the line was at once going to be destroyed, but who has been hurt? Who is about to be killed?"
The answer is that nobody had been hurt or was about to be killed. Had none of them committed adultery, or was it just not known? No, in the same talk he stated "I mention this to inform the people, that they may understand what they should do with regard to the law of God, and the transgression thereof. The law is very strict; and in this congregation there are men and women who, with uplifted hands to heaven, before the Father, the Son, and all the holy angels, made solemn covenants that they never would do thus and so. For example, one obligation is, 'I will never have anything to do with any of the daughters of Eve, unless they are given to me of the Lord.' Men will call God to witness that they never will transgress this law, and promise to live a virtuous life, so far as intercourse with females is concerned; but what can you see? A year will not pass away before some few of them are guilty of creeping into widows' houses, and into bed with the wives of their brethren, debauching one woman here, and another there. Do we enforce upon them the strict penalty of the law?"
Brigham Young did teach that when the full celestial law was both known and the children had been raised up knowing it, then such a thing would be part of it. But he also stated, in the same talk, that "it will never come until the inhabitants of the earth, and especially those who have been gathered together, have a sufficient time to be educated in the celestial law, so that each person may understand for himself."
I have written elsewhere explaining that when he speaks of the celestial law, he means a great deal more that what we currently enjoy. That is a day when all saints are as prophets. It is a day in which no man needs to say to his neighbor "know thou the Lord" because all will know him from the least to the greatest and the knowledge of the Lord will cover the earth as the waters cover the sea. And in a day like that, with that degree of light and knowledge among all the members, one may well expect that the penalty for adultery falling from that level of knowledge would be severe.
Which is what Brigham Young is teaching. Such a penalty is only exacted when there is such tremendous light and knowledge among the people that it really is a violation in direct opposition to even common sense, that it becomes a sort of treachery. It is analogous to the terms on which one becomes a son of Perdition. Becoming a son of perdition requires turning to fight against God after having come up into the presence of the Son. The sort of blood atonement Brigham Young speaks of is the penalty in a day and among a people who are so spiritually enlightened that adultery is similarly a treacherous rebellion. As we come to understand the principles on which the world runs, it becomes more and more clear to us that sexual misbehavior stands in opposition to joy in intimacy. The two are in conflict.
He also teaches that the atonement doesn't cover the breaches of individual covenants, e.g. if someone has gone to the temple and then commits adultery. This really rubs those who have taken on protestant ideas about the atonement the wrong way. Brigham Young asserts that such people must atone with their own blood. But he makes very clear that it isn't by the shedding of their own blood. In fact, he makes it clear that they atone by their suffering in mortality both through whatever punishments God sees fit to inflict by his own hand, as well as through the suffering of their own conscience. THIS IS AN IMPORTANT DIFFERENCE. When he says they must atone by their own blood, he is very clear that it is not by the SHEDDING of their blood, but by their suffering in mortality for their sins.
So there are two distinctions between the usual misconception and what Brigham Young puts forth as the correct understanding. (1) There really is a circumstance where the shedding of blood is to be required, but that circumstance is one in which a generation has grown up with the celestial law (which is far more than we currently enjoy) and so such actions are done against a perfect knowledge of the full ramifications of the deed (which we do not now have as members), and (2) there is still a sense in which people even in his day and ours must atone for with their own blood for adultery in violation of temple covenants, but it does not involve the SHEDDING of their own blood. It involves whatever suffering of conscience they go through to repent as well as whatever punishment God sees fit to inflict directly by his own power.
Note that this doctrine has ceased to be taught not because it is wrong, but because it is probably not strictly necessary for the saints to know about. Especially if they are unprepared.