But Mathieu knows even his words might not help.
Mathieu nearly lost a chance at an NFL career because of marijuana use in college. Gordon, who is facing a possible year-long suspension for violating the NFL's substance abuse policy, was arrested on Saturday and charged with DWI.
"Me, having been through it and having a little bit of experience with that, I don't think anybody in the world could possibly tell him anything," Mathieu said on NFL Network's "NFL Total Access" on Tuesday night. "No one could tell me anything when I was going through it. I had to figure it out for myself. Hopefully he will get the point.
"Hopefully he will get the message, but most of the time it takes for people to hit rock bottom for them to start believing in their self and start seeking help. A lot of people can reach out to you, but that doesn't mean you always take that help and take that advice. He just has to want it for himself."
Mathieu was at the same crossroads Gordon is facing -- one that can ultimately dictate whether Gordon has a future in the NFL. For Mathieu, there was a moment when he realized his life needed to change.
He was suspended for the 2012 season at LSU for failing multiple drug tests before he was arrested on charges of marijuana possession.
After falling to the Cardinals in the third round of the 2013 NFL draft, Mathieu became one of the league's top defensive rookies and a starter in Arizona's secondary until he tore his ACL and LCL in Week 13.
Mathieu hasn't been in trouble off the field as an NFL player.
"You have to weigh your pros and your cons," Mathieu said. "What do you want to be in life and who do you not want to be in life? You have to add all of those things up.
"I'm pretty sure who you want to be in life will weigh a lot more than who you don't want to be in life. Hopefully he can get that. I'm still young myself; I don't know too much about it, but I do know that it takes a lot to look in that mirror and fix yourself."