The photo shows Biel hugging Timberlake from behind. "She's got my back," Timbelake wrote in the caption.
Biel has also posted a few videos and photos from the tour. When the tour kicked off, she posted a video showing her singing along to "Morning Light."
"There's nothing better than watching your man do what they've been put on this earth to do," Biel wrote on March 13. "I'm so proud of you, man of the woods!"
Timberlake and Biel have been married since 2012 and are parents to Silas, whose name was an inspiration for Timberlake's new album Man of the Woods. Timberlake told Beats 1 Radio that he found a site listing the original Latin meaning for "Silas" as "Man of the Woods."
"I talk about every [album] before Man of the Woods as aspiration and then Man of the Woods really is inspiration because when you have kids, all of a sudden you're faced with your own childhood, good and bad," the 37-year-old Timberlake said in January. "And, 'Am I going to completely mess this kid up?...I feel like the success of parenthood is feeling like I failed all day today, but I get to wake up tomorrow and do it again and hopefully they turn out to be a good human being."
In an excerpt from the book The Nannie Connie Way: Secrets to Mastering the First Four Months of Parenthood by Connie Simpson, the couple revealed that Silas was born via an emergency C-section. The couple had hoped for a natural birth at home, but the plans fell apart.
"When all our plans fell apart and the serene, natural childbirth we had envisioned ended with a transfer to the hospital and an emergency C-section, we arrived home exhausted, disillusioned, and totally in shock," Biel said in the excerpt published by Entertainment Tonight last week. "I was obsessed with everything organic, toxin-free, natural, and homeopathic for our kid, who came into this world in an operating room through an incision. I was a dictator, making myself and my husband insane!"
Silas celebrates his third birthday on Sunday, on the same day his dad performs in Montreal.
Timberlake continues the North American leg of the Man of the Woods tour through June 2 in Philadelphia. After a couple of weeks off, he heads back on the road in Europe. He returns for more U.S. dates in September.
As for Biel, the 36-year-old actress recently appeared in USA Network's The Sinner, which earned her a Golden Globe nomination.
Photo credit: Instagram/ Justin Timberlake