Now at that point in the text, I rather expect that many modern teachers and even many members mostly feel that the Lord has been very down to earth about the realities of human folly among his church members. Many might feel like this is the time to bring up a statement about the church not being a place for perfect people to think perfect thoughts, but rather the church is a hospital for sick people.
The Lord, however, has a different take on the matter. His conclusion is:
63:19 And now behold, I, the Lord, say unto you that ye are not justified, because these things are among you.
Now this is startling stuff. This is God, speaking to his church, and he tells his church "ye are not justified" and the reason is "because these things are among you.". Wow.
Now, if we had been members when such a revelation was given we should be desperately casting about in our minds what we could do about it. God has just told his church that, as far as he is concerned, it is not justified. That is a big deal.
The message here is that when those who are living so they will not enjoy the first resurrection but will instead be cast into the lake and fire and brimstone are numbered among the church members then God's church is not justified in his eyes. God says, to his church as a whole, that they are not justified because those things are among them.
And what solution is there? Well, if you were someone doing things that would send you to hell then you could repent. But otherwise, what are your options? Surely the Lord provides a way for his faithful church members to create a church that he will say is justified. Of course he does. but there are only two things to be done:
1. Preach repentance.
2. Cast out those who are doing the things the Lord listed and will not genuinely repent.
That is it. Those are all the options. Preaching repentance can make a difference. But it is very unlikely to solve the whole problem. We take lightly our duty to excommunicate those who are misbehaving in the church. And in D&C 63 we get the Lord's perspective on it, and it is radically different than our own inclinations.
We see that in other scriptures that convey the same message. We read it in Jude speaking of those men who were in the church teaching that lasciviousness was acceptable and denying Christ. He writes:
Jude 1:12 These are spots in your feasts of charity, when they feast with you, feeding themselves without fear;...
We must be more concerned with pleasing God than with appearing merciful by man's measure. We must not fool ourselves into thinking it is charity to offend God by allowing the things he has condemned to remain among us. We may be tempted to think that because we are the true church, that we cannot be cut off from our God. But God says otherwise in no uncertain terms:
D&C 63:63 Wherefore, let the church repent of their sins, and I, the Lord, will own them; otherwise they shall be cut off.
Therefore let us not bask in false pride that, being his church, we do not need to worry about whether our members are apostate or doing the very things for which men will be cast into the lake of fire.
What greater concern have we, as a church, than whether we are justified in the eyes of our God?