Speaking on Undisputed -- Fox Sports 1's new show featuring Skip Bayless, Shannon Sharpe and Joy Taylor -- Lewis, who played in the NFL from 1996-2012, offered some constructive criticism for Kaepernick:
"My only advice to Colin Kaepernick is this, listen: I understand what you're trying to do, but take the flag out of it," Lewis says. "I have uncles, I have brothers who walked out of my house going into the military that said 'I will never see you again.' To understand that, I will always respect that part of what our patriotism should be and that's the side, I think if Colin really just steps back, because to affect change, if you don't have a real solution, if you ain't seen as a true activist to go into these hoods and do these things on a daily basis and not just jump up and protest because you're sick of this one thing … we've been sick of racism for 400 plus years."
— UNDISPUTED (@undisputed) September 8, 2016
Lewis, 41, is 13 years older than Kaepernick, but they faced off in Super Bowl XLVII when the Ravens beat 49ers.
The 49ers open the season on Monday Night Football, with Kaepernick listed as the backup quarterback to Blaine Gabbert.
Here is the full clip of Lewis' appearance on FS1:
-- Follow Jeffrey Eisenband on Twitter @JeffEisenband.