We believe Joseph Smith was a false prophet. A new Testament prophet that Paul wrote about in Ephesians isn't the same as the Prophets of the Old Testament. Our belief is salvation is only found in Jesus. There are no ordinances or works that I can do to earn eternal life. I'm sure you've heard this before.
What is the difference between a New Testament prophet and an Old Testament prophet? To me, if God calls a person to be a prophet, it doesn't matter whether they were in the Old Testament or New Testament, a prophet of God is a prophet of God. Many non-LDS faiths have painted us as if we believe in saving ourselves by our works. That is so far from the truth. Without the atoning sacrifice of Jesus Christ, it would not matter if we received all the ordinances and did all the works that are possible to do, we would still be unprofitable servants. This is taught in the Book of Mormon:
Mosiah 2:21
21 I say unto you that if ye should serve him who has created you from the beginning, and is preserving you from day to day, by lending you breath, that ye may live and move and do according to your own will, and even supporting you from one moment to another—I say, if ye should serve him with all your whole souls yet ye would be unprofitable servants.
We believe that it is God himself that requires us to receive ordinances and do good works before he will grant his saving grace upon us. It is not our works that save us but they are required of us before God will grant his grace. One such work is "repentance". If we do not repent, God will not save us.
Luke 13:3,5,27
3 I tell you, Nay: but, except ye repent, ye shall all likewise perish.
5 I tell you, Nay: but, except ye repent, ye shall all likewise perish.
27 But he shall say, I tell you, I know you not whence ye are; depart from me, all ye workers of iniquity.
The Lord also requires us to receive his ordinances.
John 3:5
5 Jesus answered, Verily, verily, I say unto thee, Except a man be born of water and of the Spirit, he cannot enter into the kingdom of God.
Here the Lord teaches that unless we receive baptism of water and the laying on of hands for the gift of the Holy Ghost, we cannot enter into the kingdom of God. So even though our works do not save us, they are required of us before the saving grace of Jesus Christ will be granted unto us. So often the non-LDS point to the following verse to justify that we do not need to do works because they don't save us:
Ephesians 2:8-9
8 For by grace are ye saved through faith; and that not of yourselves: it is the gift of God:
9 Not of works, lest any man should boast.
This verse tells us that we are saved by grace alone and not by our works. However it does not teach that we should not do good works. The very next verse tells us that we are created to do good works.
Ephesians 2:10
10 For we are his workmanship, created in Christ Jesus unto good works, which God hath before ordained that we should walk in them.
So even though we are saved by grace alone, God does require that we perform good works before he will grant his saving grace upon us. Verse 8 tells us that we are saved by grace through faith. The Apostle James tells us that we cannot even have a true faith without good works:
James 2:14-26
14 What doth it profit, my brethren, though a man say he hath faith, and have not works? can faith save him?
15 If a brother or sister be naked, and destitute of daily food,
16 And one of you say unto them, Depart in peace, be ye warmed and filled; notwithstanding ye give them not those things which are needful to the body; what doth it profit?
17 Even so faith, if it hath not works, is dead, being alone.
18 Yea, a man may say, Thou hast faith, and I have works: shew me thy faith without thy works, and I will shew thee my faith by my works.
19 Thou believest that there is one God; thou doest well: the devils also believe, and tremble.
20 But wilt thou know, O vain man, that faith without works is dead?
21 Was not Abraham our father justified by works, when he had offered Isaac his son upon the altar?
22 Seest thou how faith wrought with his works, and by works was faith made perfect?
23 And the scripture was fulfilled which saith, Abraham believed God, and it was imputed unto him for righteousness: and he was called the Friend of God.
24 Ye see then how that by works a man is justified, and not by faith only.
25 Likewise also was not Rahab the harlot justified by works, when she had received the messengers, and had sent them out another way?
26 For as the body without the spirit is dead, so faith without works is dead also.
So we see from this verse that you cannot even have a true faith without doing good works. Yet faith is required before the Lord will grant his saving grace upon us. We do not earn salvation by doing good works. We simply do good works that we might receive the grace that Jesus promises us if we simply do what he asks of us. Without Jesus' grace, all the works and ordinances will get us nowhere. It is likened unto a 5 year old child who wishes to go to his grandparents for the weekend. His father tells him that if he cleans his room, he will drive him 50 miles to his grandparents for the weekend. The 5 year old cannot get to his grandparents without his parents taking him there. No matter how many times the child cleans his room, he can never get there on his own merit. He is reliant of his parent to get to his grandparents home. His efforts or works do not get him there. Only by fulfilling the wishes of his parents does he have the promise of getting to his grandparents home. It is only through the faithfulness of his parents that he is able to get there. It is the same with the Christ and his gospel. We can do all that we can do but we are still unprofitable servants without the saving grace of Jesus Christ. However, we must fulfill the works that he has given us to do before he will grant his grace upon us. That is how we view faith, works, and the saving grace of Jesus Christ. He has given us commandments to keep and we must fulfill those commandments such as repentance and keeping his ordinances before he will grant the grace unto us to enter into his kingdom.