Doctrine and Covenants 20:30-34 -- On Taking Heed

"And we know that justification through the grace of our Lord and Savior Jesus Christ is just and true;
And we know also, that sanctification through the grace of our Lord and Savior Jesus Christ is just and true, to all those who love and serve God with all their mights, minds, and strength.
But there is a possibility that man may fall from grace and depart from the living God;
Therefore let the church take heed and pray always, lest they fall into temptation;
Yea, and even let those who are sanctified take heed also."
Doctrine and Covenants 20:30-34


Overall this scripture is talking about the atonement, and that Christ works to save us all, but that we still need to be careful to repent and not to reject Christ's gift.

If we break it down a little bit more, it is talking about two parts of the atonement, justification and sanctification.  Justification is basically the removal of sin, and sanctification is purification and perfection.  I think it is very similar to how we talk about another view of the two parts of the atonement... overcoming physical death and overcoming spiritual death.  The first is a basic truth... God can pardon our sins (pardoned meaning forgiven without removing the law, but acknowledging that we broke it) because he paid the price for us and has power over death.  The second is an opportunity for us to rise from that sinless state and to build on that foundation and do more, learning to love and to become the type of people that can live in a perfect society, and as we learn that lesson, then we will gain the opportunity to actually become part of one, in the Millennium or afterward in heaven.

I think it is especially important to heed the last warning, that even if we think we're already sanctified and ready for that kind of society, we still need to be careful not to be overconfident in our own righteousness.  A little pride has ruined a lot of perfect societies of the past, and be need to be extra careful of that.  Today, let's believe in Christ's atonement with everything that we are, and work towards sanctification and eternal life, working to be able to return to the presence of God, and careful not to fall into temptation.