The Nephite scripture is much more clear about the pre-mortal role of Jehovah than is the ancient Israelite scripture. The Nephites knew that Jehovah would later be known as Jesus Christ. They knew that he was creator of heaven and earth and therefore the Father of all things. They knew that he was a personage of Spirit until he took upon him flesh and blood. All of these truths were given to them because of their faith.
Today, we have the same testimony of the Savior as given by his holy Apostles, "He was the Great Jehovah of the Old Testament, the Messiah of the New. Under the direction of His Father, He was the creator of the earth. 'All things were made by him; and without him was not any thing made that was made' (John 1:3)…We bear testimony, as His duly ordained Apostles—that Jesus is the Living Christ, the immortal son of God. He is the great King Immanuel, who stands today on the right hand of His Father. He is the light, the life, and the hope of the world." ("The Living Christ: The Testimony of the Apostles," Jan 1, 2000)