"People in New York just need to trust the fact that he knows more about basketball than any of them put together," Bryant said after he and the Los Angeles Lakers lost to Jackson's Knicks on Sunday night.
Bryant later added: "In my opinion, he's the greatest coach in any profession. Ever."
The Knicks have won three of their past five but at 28-40 are likely to miss the playoffs for the third straight season. Their record since the start of the 2014-15 season is 45-105, and Jackson has drawn criticism for the team's struggles.
The 70-year-old Jackson said Friday that he hopes to continue to build the Knicks roster via free agency this summer. The club will have at least $18 million in cap space.
"We definitely [have] ideas about how to help this team. I don't think there are secrets or mysteries," Jackson said. "We have agents calling us up all the time trying to sell their players to us, so I think we're going to do just fine in free agency."
Jackson will also have to hire a coach in the offseason. He fired Derek Fisher -- the first Knicks coach he hired -- after the club spiraled through a 1-9 stretch prior to the All-Star break.
New York is 5-9 under interim head coach Kurt Rambis, who Jackson said is "fully capable" of coaching the team next season.
Jackson is under contract for three more seasons, so he will have an opportunity to turn things around. But his lack of success in New York thus far is new territory.
Jackson, who won an NBA-record 11 titles as head coach of the Lakers (five) and Chicago Bulls (six), acknowledged as much when speaking with reporters Friday.
"April 12, our final game, I've never been in these positions before," Jackson said. "It's like going on spring break and I don't have any place to go."
Bryant said Jackson's task as president of the Knicks isn't all that different from the challenge he faced as a head coach.
"As a coach you obviously have more control over the outcome, to a certain extent," Bryant said. "What he does now is really understanding the personnel. But that's no different than what he did as a coach. As a coach, he would have broke down the players, understood the players. That's the same thing he has to do as a GM."
Bryant also disagreed with the theory that Jackson's success was a product of his players. Jackson coached Michael Jordan and Scottie Pippen in Chicago and Bryant, Shaquille O'Neal and Pau Gasol in Los Angeles.
"I think we don't win any of those championships without him, I don't think Chicago wins any of those championships without him," Bryant said. "And, I heard the argument that's the silliest thing I've ever heard, that Phil won because he had great players. No s--- Sherlock. What are you going to win with, a bunch of scrubs? It's like the silliest argument in the world to me."