What does signed sealed and delivered mean in a song?

In a song, "signed, sealed, and delivered" typically refers to a commitment or promise that is fully finalized and guaranteed. It conveys the idea of a relationship or emotional bond that is official and irrevocable, suggesting that feelings are strong and genuine. The phrase evokes a sense of certainty and assurance, emphasizing that the singer is completely devoted to their partner. It has become a popular expression in music, symbolizing love and dedication.