"This song is a love letter to my wife," Nick said of "I Believe" on their comeback album, Happiness Begins. "I'm so excited to play it on tour."
"We listened to it a lot on your bachelor party," Joe Jonas chimed in about the song. "It sounds even better by the beach."
"It does," Nick agreed. "So try that."
On the romantic track, Nick sings about sticking with his love "through the good and the bad times."
"Every night every day; how about every lifetime? / Yeah I know what they say, and that's fine / 'Cause I'm here to stay through the good and the bad times / Baby save me a space in your mind," Nick sings. "Call me crazy / And people say that we move too fast / But I've been waiting, for a reason / Ain't no turning back / 'Cause you show me something I can't live without."
Read more on Priyanka Chopra and Nick Jonas' love story, below!