The insight that my friend had was that God will keep and preserve those things that are His, because they are His, and that included more than just murals and buildings. As I thought about this I thought about the covenants that we make as members of the Church and how we covenant with God to keep His commandments and to obey His Law, and in return he will make us His. That may seem like a simple thing but when we consider it that is a very significant thing. When we make covenants to God that we will obey His Law and keep His commandments then in return He will own us, keep us, and preserve us. The strength of this sealing is something beyond our comprehension. This is a sealing and a power that stretches beyond death and hell to preserve those that are owned by the Lord. It is a covenant that He will not lightly abandon. Those that make this covenant will be brought back to the presence of God because they are His and he will not let them go. They will be brought back, in life or death, to the One who owns them.
"Verily, verily, I say unto you, if a man marry a wife according to my word, and they are sealed by the Holy Spirit of promise, according to mine appointment, and he or she shall commit any sin or transgression of the new and everlasting covenant whatever, and all manner of blasphemies, and if they commit no murder wherein they shed innocent blood, yet they shall come forth in the first resurrection, and enter into their exaltation; but they shall be destroyed in the flesh, and shall be delivered unto the buffetings of Satan unto the day of redemption, saith the Lord God." (D&C 132:26)This does absolve them of their responsibilities, nor does it give them a free pass, but God will preserve that which is His, and He will not let them go. But what about those who have not yet made this covenant? What about the children who die before they can be sealed by this power? Or those children who reject the message of the gospel and do not continue in the faith? When a man and a woman are sealed by the covenant, that power covers those who belong to the parents, the children. They too shall be brought back by the power of the covenant, either in life or in death and they shall not be lost. This is the power of the covenant and the sealing that is given to those who faithfully make and keep this covenant.
"For the mountains shall depart and the hills be removed, but my kindness shall not depart from thee, neither shall the covenant of my peace be removed, saith the Lord that hath mercy on thee." (3 Nephi 22:10)Though all things shall fail, this covenant will not fail nor be removed, for the Lord is merciful and will keep that which is His.