We believe all that God has revealed, all that He does now reveal, and we believe that He will yet reveal many great and important things pertaining to the Kingdom of God.
God continues to speak to us and reveal His word. His words and works never cease. In regards to the scriptures, Latter-day Saints do not believe in a closed canon. God is not limited to one book or one period of time. But just as He has done since the beginning of time, God still speaks to prophets today, revealing His word through them.
I’m going to use some verses from the Book of Mormon to explain this, since they state it better than I ever will. It’s a bit to read, but it’s worth it.
Thou fool, that shall say: A Bible, we have got a Bible, and we need no more Bible. Have ye obtained a Bible save it were by the Jews?
Know ye not that there are more nations than one? Know ye not that I, the Lord your God, have created all men, and that I remember those who are upon the isles of the sea; and that I rule in the heavens above and in the earth beneath; and I bring forth my word unto the children of men, yea, even upon all the nations of the earth?
Wherefore murmur ye, because that ye shall receive more of my word? Know ye not that the testimony of two nations is a witness unto you that I am God, that I remember one nation like unto another? Wherefore, I speak the same words unto one nation like unto another. And when the two nations shall run together the testimony of the two nations shall run together also.
And I do this that I may prove unto many that I am the same yesterday, today, and forever; and that I speak forth my words according to mine own pleasure. And because that I have spoken one word ye need not suppose that I cannot speak another; for my work is not yet finished; neither shall it be until the end of man, neither from that time henceforth and forever.
Wherefore, because that ye have a Bible ye need not suppose that it contains all my words; neither need ye suppose that I have not caused more to be written. (2 Nephi 9:6-10)
The Church of Jesus Christ of Latter-day Saints is a progressive church. By progressive I mean literally it is a church of progress. Living prophets and apostles do exist, and they are the Lord’s instruments in revealing His word to us. If God truly is the same yesterday, today, and forever, His works cannot and will not ever cease.