The 35-year-old singer said Timberlake and Biel know each other so well that they're destined to stay together, reported Contactmusic.
"Not much is going to change. He's a great dude, and he's very focused on what he does and everything else, and I'm sure this will bring out the best. He's been with her for a long time, so it's basically a piece of paper. That's what me and my wife (Kelly Baldwin) were like, and we've been together over 18 years now," he said.
When asked what advice he'd give the 'Social Network' actor, who recently enjoyed a bachelor party in Las Vegas and Mexico, he said, "just enjoy life, because it goes by way too fast."