Justin, 38, who has never been one to be shy about his love for his wife, was extra candid with his fans on Jessica's big day.
"My partner in this thing called life...you are the most wonderful human I have ever met," the Man of the Woods singer wrote. "You make me smile, laugh, and love life more than I knew I could."
"I cherish every moment with you and can’t wait to spend so many more years doing the same...but, new," he added alongside a small slide show of pictures. "Happy Birthday, you GOD OF ALL SMOKE SHOWS!! Love, Your Huz."
- Jessica Biel Gushes Over Husband Justin Timberlake On His Birthday — See The Adorable Photos!
- Britney Spears Reflects On Justin Timberlake Relationship Before Bizarrely Teasing Her Terrible Tattoo: 'It Really Sucks!'
- Jennifer Lopez & Ben Affleck, Blake Lively & Ryan Reynolds And More! Hollywood's Favorite Couples
The Sinner actress wrote a similarly intimate message for Justin's 38th birthday on January 31. "I am the luckiest human around to have the honor of hearing your jokes, your words, your voice, every day of my life," she wrote at the time. "Happy birthday to the man of my blue ocean dreams. I love you."
As OK! readers know, the A-lister couple walked down the aisle in October 2012 and welcomed their son, Silas Randall, into the world in April 2015.
What do you think about the loving message Justin posted for Jessica's birthday? Let us know in the comments below!