Since you are asking me about what we believe, your question should be: Can I show it from the LDS Scriptures?
Click on the link at the end of post #15. You will find there the verses I quoted in #15, and more. I stopped at the end of the Bible passages in that one particular topic because Terry was asking for Biblical indications.
The fundamental questions are, as always, is Joseph Smith a true prophet of God, a true apostle of Jesus Christ, with the same authority to give us these Scriptures that the ancient apostles had? Are the LDS Scriptures the Word of God? Jesus said, "Ask, and it shall be given you." The Holy Spirit bears witness, as do I, that these things are true and of God.
I think you know that this is our practice, rather than proof-texting.
Matthew 7:7-11
7 Ask, and it shall be given you; seek, and ye shall find; knock, and it shall be opened unto you:
8 For every one that asketh receiveth; and he that seeketh findeth; and to him that knocketh it shall be opened.
9 Or what man is there of you, whom if his son ask bread, will he give him a stone?
10 Or if he ask a fish, will he give him a serpent?
11 If ye then, being evil, know how to give good gifts unto your children, how much more shall your Father which is in heaven give good things to them that ask him?
D&C 46:9
9 For verily I say unto you, they [the gifts of the Spirit] are given for the benefit of those who love me and keep all my commandments, and him that seeketh so to do; that all may be benefited that seek or that ask of me, that ask and not for a sign that they may consume it upon their lusts.
(Lurkers, get ready for the burning-bosom jokes, and claims that this is asking for a sign.)