And oh, my heart was flawed I knew my weakness
So hold my hand, consign me not to darkness.
The narrator now appears to be talking to God. He might be praying, telling God about the sinful act, asking God to forgive him and not to abandon him, to consign him not to darkness.
To help improve the meaning of these lyrics, visit "Broken Crown" by Mumford & Sons Lyrics and leave a comment on the lyrics box