Dan Reynolds has spent much of his life fighting depression. For a long time the Imagine Dragons frontman struggled with the fact that rather than the band's music, he had become the story. "It was hard for me," he admitted to The Sun. "I would get through all of these interviews and then they would write 'Dan Reynolds. Depressed.'"
However, Reynolds is now in a better place and during this song he uses the analogy of the river meeting the sea, to describe the new journey that he's on. "Now, I've gotten to a place where I don't see it as a weakness. I see it as part of who I am," he explained. "For me I have just accepted it and I know my pitfalls as I am growing older. I know the things that bring me happiness and the things that help stabilize me and I am not afraid to sit down with a therapist and talk about my problems."
Jackson Stewart from Payson, Ut If more was understood about the Church of Jesus Christ of Latter-Day Saints, and the band's connection with it, it would be easily understood as someone in the shoes of Laman, a man who lived 600 years ago in the Book of Mormon. In 1 Nephi 2:8-10 Lehi (Laman's Father and Prophet) names a river after him, and hopes that he can be mighty and holy like that river by saying "O that thou mightest be like unto this river, continually running into the fountain of all righteousness" and continues to say "O that thou mightest be like unto this valley, firm and steadfast, and immovable in keeping the commandments of the Lord".
Lehi being a devoutly religious man wants his son to be a good man, but with the information that is know about him, he's not that great of a guy. From always murmering against his father to trying to kill his brother on multiple occasions, as well as his father once, hes not as Dan Reynolds buts it "with the faithful ones". From and outsiders standpoint tho, hes not all that bad. I mean every time hes given a commandment, he does it, just not with the right attitude, which is why Dan Reynolds and myself included related to Laman more often than his more righteous Brother Nephi.
This is why the song is title "mouth of the River" to be modern and genetic enough for everyone to relate to, but to those who are members of the Church of Jesus Chris of Latter-Day Saints, or at least read the Book of Mormon, can relate with Dan Rrynolds and a deeper more spiritual level.