By virtue of the Fall, all suffer spiritual death which is defined as being cut off from the presence of the Lord. As the brother of Jared reenters the Lord's presence, he is of necessity redeemed from that Fall. The same could be said of any prophet who, while in mortality, stood in the presence of God.
But more interesting is the Lord's statement about knowledge. It was because the brother of Jared knew certain things that he was brought back into the presence of the Lord. What did he know? He knew that God is a God of truth, and canst not lie (v. 12). He knew that God is omnipotent, O Lord thou canst do this. We know that thou art able to show forth great power (v. 5). He knew that if he would believe in him that he could show unto him all things (v. 26).
When the brother of Jared saw God, it wasn't only because of faith. We have learned from his experience that it also required humility (see v. 2) and knowledge. This knowledge is not secular knowledge but that kind of knowledge which is built upon the bedrock of faith. Hereby, we learn about the relationship between knowledge and faith. Many consider them mutually exclusive concepts, but they are not. While the world asks for knowledge instead of faith, we ask for knowledge through faith.
Bruce R. McConkie
"The brother of Jared stands out as a good illustration of how the knowledge of God is gained by faith, and also of how that perfect knowledge, from a mortal perspective, replaces faith." (A New Witness for the Articles of Faith, p. 211)