One of the comments on a Mormon website says about the Book of Mormon: "Like the Bible, it's an ancient witness for Jesus Christ. Both books have changed my life for good."
They might have changed this person's life; but the bottom line is, the "Book of Mormon" did NOT come from God because the Bible commands us not to add to, or subtract from His Torah (first five Books) or from the Book of Revelation.
Deuteronomy 4:2 2 In order to obey the mitzvot (commands) of ADONAI your God which I am giving you, do not add to what I am saying, and do not subtract from it.
Revelation 22: 18 I testify to everyone who hears the words of the prophecy of this book: if anyone adds to them, God will add to him the plagues which are written in this book; 19 and if anyone takes away from the words of the book of this prophecy, God will take away his part from the tree of life and from the holy city, which are written in this book.
The Bible is the ONLY Word that man is supposed to follow. The Torah shows us how to live; it contains all YHWH's "do's and dont's, yet it seems most people have never understood that concept. He walked with Adam and Eve in the Garden of Eden and told them how to live; yet they decided to listen to the serpent instead. He brought the captive Hebrews out of Egypt, revealing Himself in a pillar of cloud by day and a pillar of fire by night - and for forty years He even gave them food to eat for which they didn't have to lift a finger while they were concentrating on learning His ways - yet they continuously rebelled.
He sent His only "Son" Yeshua (Hebrew for "YHWH is Salvation"), so that mankind could learn from God face-to-face. Yeshua showed YHWH's people who God is and how to properly obey and worship Him, and then He offered Himself as our final SIN sacrifice. Today, all we have to do to gain eternal life is to believe in YHWH and in Yeshua's Sacrifice, repent, and live our lives in a set-apart manner according to His Divine Instructions in Righteousness (Torah).
But still today - thousands of years later - mankind continues to rebel against God. Right now we are in the end times; which can be likened to "as in the days of Noah" when God decided to flood the earth to destroy all but one righteous family. Decadence and "tolerance" are today's "buzzwords." Anyone who attempts to live a "godly" life is maligned, ridiculed and scoffed. Various "religions" abound. Christianity alone has nearly 40,000 different "denominations"....Which one did Yeshua bring?
Despite Torah's warnings to let God's people know they are to stay away from idols, other gods and paganism, along comes Joseph Smith Jr. (on April 6th, 1830 in Palmyra, New York) and tells the world he had visitations from the spirit world where he discovered he was supposed to start a brand new religion that not only contradicted, but added to the Torah, as well as the rest of the Bible!
Smith ended up writing more than 60 false prophecies, as well as scores of verifiably false historical and archeological statements that comprised the Book of Mormon and, what's more, he claimed to have discovered the Mormon writings written around 600 A.D. in "King James" style, no less! (Ironically, that's approximately the same time Islam was born, as well!)
Here's something else: YHWH says if you are a prophet, every single word uttered in His Name will be accurate:
Deuteronomy 18:20 "The prophet who shall speak a word presumptuously in My name which I have not commanded him to speak, or which he shall speak in the name of other gods, that prophet shall die."
If Isaiah, Daniel, Jeremiah, Hosea, and other "OT" prophets, had spoken ONE single inaccurate word from YHWH, they would have been killed and their writings destroyed. Mr. Smith, upon whose writings the Mormon church was founded, is a false prophet because - if nothing else! - his Book of Mormon "added to" Scripture.