"Safe & Sound" is a song that speaks of comfort, protection, and hope amidst danger, darkness, and despair. The lyrics suggest a person who is comforting and consoling someone who has gone through a difficult time and is afraid of what might come next. The narrator reminds this person of a vow made to never leave them alone, and assures them that they will be safe and sound. The chorus's repetition emphasizes the sentiment of reassurance that nobody can hurt them now, and that they will be safe and sound.

In the second verse, the lyrics depict a war that's outside and raging on, and the narrator encourages the listener to hold on to this lullaby, a song that can bring peace and comfort even when the music stops.

The song's overall meaning could be interpreted as a message of hope and support for anyone who's suffering from emotional pain or trauma during a difficult time in their life, reminding listeners that even in the darkest of moments, they are not alone, and that they can find light and comfort in the company of others.