The superstar shared a quartet of photos in a Father's Day Instagram post that features the two of them together, although the child's face is not seen in any of the pictures.
In the shots, Timberlake's holding Silas near a microphone stand on a stage, sitting in a car with his son on his lap, looking down at him while they appear to be inside a stadium and holding his little one in his arms while rocking a hat and sunglasses.
The 39-year-old began his message by focusing on the importance of teaching children racial equality.
"Boys grow up to be fathers. I think about that a lot these days," he began. "We try to teach our son to love and to respect everyone — we teach him that all people are all created equal, and that no one should be treated differently because of the color of their skin.
"We teach him this because one day, he will go on to teach his kids the same. It's a cycle."
"And right now, as we all work to undo generations of discrimination that have plagued our system and our communities across this country... I'm reminded today that the first lessons start at home," he wrote. "Im grateful for both of my dads and my mother for teaching me those lessons from the beginning. And for listening to me when I had something to say that they hadn't learned.
"I pray for that humility with my own son. I'm grateful for my wife, who made me a father, and is my favorite person/partner/teacher/friend in all of it. I'm grateful for my son, who is always ALWAYS teaching me right back."
He ended his post with words of optimism that parents will not let up in the fight in leading the way for their kids.
"Happy Father's Day to all the Dads out there. While we owe our sons and daughters these lessons in the places where the doors close at night, I hope you are as inspired as I am to make them THE TRUTH in the places that same door opens every morning and we send them out to discover," he wrote. "There's more to do. And we are built for it. After all, we are the Dads. Sending my love to you and yours."