Jesus says he is the Father in the Book of Mormon

Ether 4:12 [BOM}
“And whatsoever thing persuadeth men to do good is of me; for “good cometh of none save it be of me. I am the same that leadeth men to all good; he that will not believe my words will not believe me—that I am; and he that will not believe me will not believe the Father who sent me. For behold, I am the Father, I am the Light and the life and the truth of the world.”
This is crass Modalism, Sabelienism, Patripassionism. This is sheer nonsense! It isn’t quite the same nonsense Mormons officially believe in. But it is nonsense nonetheless. I’m guessing Spaulding, or Jr. editing, wanted to sound somewhat Trinitarian here. But it falls way short. This is one God and one person at the expense of the other person’s of the trinity. This is more or less the Muslim misconception with the Christian concept of the Triune God. They are prone to ask “Who did Jesus Pray to?” They cannot comprehend that when we say 3 persons 1 God we actually mean 3 distinct and separate persons who communicate with each other and not one person who is God, expressing himself in 3 different ways.
Jesus can be God, co-eternal with him, of the same substance with him, very God of Very God as we say in the Nicene Creed, which is really the place to go when wanting to understand what the church believes about the Trinity, well that and the Athanasian Creed. One can easily then look at scripture and find the passages that support it, or read Athanasius and Gregory of Nazianzus who will also point you to the pertinent scriptures and explain to you why this matters. Jesus can be God that is without being the Father. In fact, the fact that he is the Son demands that he not be the Father. This is especially true when like mormons you believe that the Father has a body like ours. That concept renders the entire idea of the Trinity inconceivable and impossible. If the Father has a body like ours and the son has a body like ours than they are of necessity to ontologically distinct beings, and not just separate persons who share the same divinity and are of the same divine substance sharing an ontological unity therein.
But why does all this matter? I think the common way to think about this is in regards to the law. Typically, we think of it in this way, a false concept of God is a false god, and so to deny the Trinity is to deny God, and break the first commandment. True enough. But it is more than that. It is that the false concept of God actually prohibits the gospel and turns it into something other than good news.
Rather than God forgiving our sins and justifying us with his death and resurrection, when Jesus is no longer God, the “gospel” is no longer good news. Instead as with classical Arianism, contemporary counterpart of Mormonism also changes the purpose of Christ. Jesus comes to show us how we can save ourselves. And he didn’t wait to long to do that! What did people do before his example? Well then you get into this silly dispensationalist stuff, where what worked before no longer works. The reality is it never worked to begin with, Law never has. If Jesus was our example we are all just royally screwed, we don’t live up, nor can we. But Jesus claimed to be our savior, he claimed to forgive sins, he claimed to have died in our place. This he could only do if he were at the same time, fully man, and fully God. And this he was. He was God even before he was conceived, and as God, still is God today and for all eternity. His death then, being the death of the man who was God, was a sufficient ransom for all men. He didn’t come to show us how to save ourselves, he came to save us. He does this only through the forgiveness of sins, without which we are dead. And this is why the Trinity matters, without it, you have no gospel, only law.